I noticed that too…seems wild. I’m assuming the tan part must be some sort of additional rubber plastered over the black maybe?
I’ve been using Pirelli P Zero Roads (tubes) for all of May. Decent all-rounders after using GP5Ks. Son has been running Challenge Stradas (tubeless) which roll great but have as much puncture resistance as tissue paper.
I considered getting the “all season” version of the GP5000 but ended up just getting another set of the usual S TR. Today I did a 50 mile endurance ride and it basically rained the entire time. GP5000 S TR in a 32 was still perfect.
I run both the black and tan sidewall ContiGP5k clincher tires. I’ve read that there is a difference in Crr between the black (vulcanized) sidewall, tan (painted??) sidewall but, I don’t understand why. I have both only because I buy whichever is cheapest at the time.
Anyways, I believe the new Vittoria Pro is a true skinwall tire so it should be more supple, lighter and all else equal better Crr. than a non-skinwall version. Still for the money and durability the Conti GP5K has been my go to for many years.
GP 5000 with latex. Brilliant.
Spent last year on corsa G 2.0 clinchers and latex, very good and no punctures but prefer the GP’s they felt quicker when i changed.
No way i’m spending £80 on a Corsa Pro, can get two GP 5000 for that.
Mind you I’m sure I felt the same when I switched to Corsa from GP 5000
New tyre syndrome is definitely a thing. 
I’ve never been a fan of the road FEEL on Conti GP4000 or 5000 tube tires, but have used them. Most recently I ran GP5000 with a regular tube and put Orange Seal in the tube, that helped seal wire flats, but did not stop flats from nails and screws on the road.
I ride about 400 hours a year all outside, and getting to the quiet roads involves county highways and there is a lot of construction where I live. Therefore a lot of nails and screws and wires and other debris along the roads. The quiet roads have “goathead” thorns, I even had one in my sandal this weekend (ouch).
For all those reasons I run tubeless and my favorite tires are:
- Pirelli Cinturato (tubeless) is my no flat option, but its slow
- Vittoria Corsa N.EXT is my latest tire to try out, very nice road feel and its sealed a couple issues (one was a construction staple stuck in the tire)
- Specialized S-Works Turbo 2BR T2/T5 (not the faster RapidAir)
FWIW I bought the GP5000 S TR and was unable to mount them without resorting to heroics. They aren’t lined, and I’m not a fan of the road feel, so these were sold.
The 5000 TL was ok but it got a ride-ending flat (yes, tubeless ride-ending flat) before 500 miles. Same with the previous generation S-Works Turbo. Same with Pirelli Race TLR. Did I mention that there has been a lot of construction in this area, for the last 20 years? Anyways, a lot of ride ending flats before adopting the Vittoria Air-Liner inserts.
Hope that helps.