I’m less impressed, the gearing is just not great. SRAM’s 10–46 cassette has road gearing for the first 10, 11 gears and then climbing gears on top. My experience with cassettes that have such gearing (Shimano 11–46 11-speed, SRAM 10–33) is that it works great for me, much, much better than tightly spaced gears on the climby end.
However, a SRAM 9–46 cassette would be killer: you could stick to the XPLR rear derailleur and get the same gear range as their MTB cassettes.
Judging by early impressions, the reviewers all noted that the lack of a clutch isn’t as much of an issue or no issue at all. On Escape Collective, they also mentioned another thing I found interesting: Shimano’s clutches are prone to rust, which explains why I have a dead mechanical XTR rear derailleur sitting in my shed. My previous LBS tried to revive it. I might give it a go, but right now I “downgraded” to XT.
Shimano is late to the game. Usually, they compensate for that with quality, polish and all. But I think they waited too long and have too much to catch up on. On the dropbar side, you can make a much better argument for keeping things wired, but they missed the bigger picture (mullet drive trains, mountain bikes, the mixing of categories, etc.) and focussed on traditional road riding. Having lived in Japan, I understand well why. MTBing is much, much less of a thing there.
What baffles me is the brakes: the regular XC brakes seem to be very meh whereas reviewers really seem to like the trail/enduro brakes. Shimano should have just ditched the old XC brake design. That would have fixed another issue: the new XTR brakes look identical to my XT M8100 brakes (apart from the logo), but they need a new brake fluid. How many riders and bike shops are going to mistakenly use the wrong brake fluid?
What I hear (not having ridden T-type SRAM drivetrains myself either) is that riders need to adjust their shifting habits and that this works very well for certain terrain. It seems once you get used to shifting under any load, it opens possibilities and changes your riding style.
SRAM has another ace up its sleeve: it can (and has) trade shifting under load for shift speed. Its 13-speed XPLR drivetrain shifts faster, but hasn’t been designed to shift under full load. It’d be nice if SRAM offered options, e. g. a 9–46 XPLR cassette which has the same range as its MTB cassettes, but faster shifting.
Or it could offer a setting and two types of cassettes (although that might lead to riders and bike shops making mistakes or deliberately combining the wrong shift option with a particular cassette).
I don’t think that matters. On all of my bikes, the smallest gears are used as overdrive gears, i. e. I’m going downhill and could use a very hard gear. The second- and third-hardest gear get much less use out of them.