Agreed. I know plenty of codebases still written in C++03 style and work fine. I'm still using 2015 edition Rust crates and they work fine. I won't say there's no cost to evolving idioms, but evolving idioms on this front means it's more of an affront to asthetics than it is to productivity or anything else actually important to business goals, IMO.

The one exception perhaps being async/await, in that a bunch of crates are making breaking API changes to accomidate it and bumping their major versions - because it's bloody useful and a bit more than your typical syntactic sugar - which means changing your code if you want to keep getting patches.