As a developer I complain that passing unique_ptr is a couple if cycles slower than it needs to be because of the ABI and I wish the committee/GCC was more aggressive with ABI breaking.

As an user I complain that I can't run linux games from 20 years ago because GCC broke the libstdc++ ABI 15 years ago and how WIN32 is the only stable unix ABI.

Luckily I'm not a compiler developer.