I was pretty disturbed to hear cycle industry propaganda talking about 'hydraulic disk brakes freeing up frame space to allow manufacturers to innovate' sounds exactly like the MTB 27.5, boost and fat and plus wheel and axle options propaganda that have been floating around the MTB industry. On my bike with alloy Campaganolo or DT Swiss rims my 105 rim brakes with stock pads in the dry have exactly the same power AND modulation as the Shimano XT and SLX brakes I've been using for years on my MTBs. But rim brakes are so easy to set up, don't drag, don't need to be bled or the disk trued, also disk brake pads are expensive and can get contaminated quite easily.
I'm not against hydraulic disk brakes, they have their place, commuting, bike-packing, gravel and very good for companies not getting sued by people using carbon rim brake wheels and can save money as you only need to replace a disk not a rim and can be more aero. However in MTB riders were duped into leaving 26 inch for 27.5. All the best wheels and tires only in 27.5. 26 inch? 'Sorry mate not available'. And now 27.5 will be phased out being replaced by 29 inch. 20mm axles 12mm axles, boost spacing, plus spacing. The cycle industry trying to make more money but creating redundant dead end standards.
In the end as I've said before there is nothing really wrong with hydraulic brakes other than the weight and extra wrenching skill needed, but my worry is that all the pros will be forced onto disks by their sponsors and then everyone else will be left being forced in that direction. Buying a bike at the UCI weight limit or getting an entry level bike upgraded to that weight will become hugely more expensive, and if you live in a fairly low rainfall country it will be an almost completely unnecessary waste of money.