Side wall tears are the only real issue in the 6 years I’ve been running road tubeless.
How to avoid the call of shame if you get a side wall tear:
Some tubeless tires seal better than others.
Admittedly I don’t run weight weenie tyres, and wouldn’t run without the flat protection, but as you (kind of) say, once a (good) tyre is sealed it doesn’t matter what’s sloshing in there or not.
It’s not something I’d do, but I have wondered about it a few times when reading weight weenie builds where the rider has chosen TPU tubes. The thing is, any tube is slower and less smooth than tubeless on the MTB.
The problem with those guys is they use the lightest of light tyres that wouldn’t hold any air without a tube anyway. They also use 2.1" tyres and clearly don’t ride technical terrain.
It was more a thought experiment. I know quite a few people that don’t believe sealant does anything to a puncture anyway. I know it can seal a good quality tyre up tight though. You could have a great, light, fast set up going sealed but dry. You’d optimise your spares for that as the plugs would be slightly less effective.
For the OP or anyone thinking about repairs. Another option for tubless repairs is the sticky patches. Not a permanent solution, but could help you get home.
For you roadies, I’d carry patches, plugs, and a Vittoria Pitstop or similar along with your inflating device of choice.
I guess here’s the way I look at it. Having a tube as insirance is great if you run tubeless, but not mandatory. In decades of riding, and 10s of thousands of miles of riding, there have been ~2 times I’ve had a situation where tire damage would not be able to be fixed by sealant or a plug. 1 was an 8" piece of steel lodged in my tire, and took a gash out of my rim tape and scraped the inside of my rim. The other was a random rock in the middle of the road I didnt see…clipped the edge of it and took a good slice on my sidewall.
I think the opposition to tubeless is more philosophical/the result of insecurity, than any real practical concern honestly.
Really? I’m sure there is some nuance in combinations, but I’ve had multiple sets of GP5K STR on ENVE hooked rims and Zipp Hookless rims and have never struggled to break the bead.
Goes back to ‘Know your stuff’ 
Between the higher pressure and sealant acting as an adhesive, I would say the most road tubeless flats that I have seen have involved some struggle to break the bead (if not outright failure).
It is a pretty well-known issue for road tubeless, IME.
I personally started packing thinner, metal tire levers to help in this regard.
In 6 years of running tubeless I’ve only had 1 tire that was hard to unseat - Vittoria N.EXT (this year). There has been a LOT of tubeless tires on this bike from Specialized, Schwalbe, Conti, Hutchinson, Vittoria, Pirelli, … Except for that 1 tire (front), I could remove all the others in my garage or on the side of the road if it mattered.
6 years tubeless and I’ve had at least 3 sidewall cuts that required a boot and a tube. And I’ve seen others suffer the same fate, I’m not alone.
strange, I can break the bead on all mine with one hand and remove them with a single tire lever. Like I said, maybe it’s peoples specific combos.
??? Road tubeless hasn’t been around for decades.
No, of course not all of that was tubeless. I was just referring to tire damage more significant than an invisible pinhole.
I just put on some gp5000 on my road bike which are notorious for being tight. Took me a couple minutes with a tire lever. I carry a tube. Have needed it once when I ripped a sidewall over 4 years. I also carry plugs.
For my gravel bike unless I’m going way out in the middle of nowhere, I don’t carry a tube on normal rides because those tubes are too big to fit in my saddle bag. My strategy there is plugs only. If I was going longer or more remote, I’d have more bags and could fit one. Same with my mountain bike. I haven’t carried a tube for that in a decade.
How TF did you not SEE the 8" piece of steel in the road to be able to avoid it? 
I kid, of course… sh!te happens.
To mirror to the OP what so many others have said throughout this thread… in my 3 years running tubeless, i’ve (thankfully) never experienced a need to even use the spare tube(s), boots and plug(s) I carry in my bag. This coming from someone that doesn’t top up nearly as much as I should, i’m sure.
At this point, I would choose tubeless any day over running tubes… especially considering my recent club century a couple weeks back. We had to stop 3 times for one of the guys in the group after he flatted while running tubes. First two times he didn’t inspect his tire well enough to remove the tiny sharp stone that pierced his 1st and then 2nd tubes. The third stop was a snake bite. The snake bite ended his day at mile 90 in frustration! He was simply fed up, so one of the other guys in the group offered to finish the ride and bring back his car to pick him up while he sat beside the road waiting.
Two days later, the title of his next Strava ride was… “Tubeless test”… he hopped on the tubeless train the next day and from what he says, he loves it!
If that’s the bar, then it’s set pretty high.
…maybe one for the manual challenge tricks? 
10 oclock at night after 4 beers, riding through an industrial corridor 
I carry 2 spare tubes and a patch kit even with Tubeless tires. If all of that fails, I deserve a ride.
the sealant in the tire tends to mean that you don’t actually become aware of a “flat” until you change your tire. I love counting all the flats I didn’t have to fix.
It’s true that TLR tires are a little harder to mount, but not that much harder.
I’ve never needed to make a call to get picked up.
It’s not really that hard to put a tube in if the plug doesn’t work.
Some guys have been in the road tubeless game since Shimano released their system back in 2006/07. Road tubeless came out, died, and then was brought back to life once UST went away.
former road tubeless user. Massive side wall slash and couldn’t plug, couldn’t get the tyre off the rim cause it was so damn tight.
back to latex tubes and clinchers and have never looked back, can always boot the tyre with a gel wrapper and get home easily.
This is the way to go. Check the sealant level regularly and carry Dynaplugs, co2 cartridge(s) and/or a small pump.
If you still want to carry tubes for emergencies, get some Tubolito s-lite tubes: very small and light, but tough enough for getting back home.
I find it impossible to remove tubeless whilst out on the road.
But it’s a very rare event given that small punctures are filled by the sealant.
And my wife, AKA “International Rescue”, is very understanding. (Though it’s a few years since I last needed her. I actually needed her assistance more regularly before I went tubeless - e.g. in hedge cutting season when I ran out of spare tubes.)