Larger tyre almost at same diameter as a 29er
I’d say 2.8 tyres are more likely to be a similar diameter to a 27.5 wheel with 2.5 tyres.
I’ll add another vote for the SolarisMax, also running 2.8 on it and it’s pretty darned good, still to try it with 29er wheels.
Nordest Bardino possibly, they do a Ti & Steel option and a variety of sizes.