I just got a 27.5 plus bike. Salsa timberjack. 2.8” x27.5 tires. I was skeptical about the heavier wheels and tires feeling sluggish but the bike is nimble and climbs great.
I have not gone tubeless yet but it is set up for it.
With the almost same diameter as a 29er and the higher colume the tires can be run very low pressure. They conform better to the texture of the trail and roll over everything.
I think it’s more about the frame than the wheel size a lot though. The timberjack has modern trail geometry with a 68 degree head tube angle and short chainstays with a longer top tube. Nice wide bars and a relatively short stem.
So different than my old 2004 Gary fisher marlin. Besides the 26” wheels I mean.