Higher end framesets will be set up for electronic only, with no provisions for derrailluer cable stops or routing. Double chainrings will die. We'll be up to 15-16 cog cassettes that your current wheelset will not fit so you'll have to buy some new ones. Rear spacing will be wider so your current wheelset won't fit that, either.
Everyone who dares to complain about those things will be looked down on and be called retrogrouches and boomers by the newer riders who are 10 years old right now.