You have to compare that to the amount of energy spent while making it 0.1% faster. On average, I'm not sure we'd be saving any energy. The one bit that would get any remotely relevant gain would be offset by lots of tools where that improvement happens once a week.

How many minutes / how much energy would it take you to setup a project, run a profiler, do the fix, run tests/CI, commit, release, etc. -vs- how much energy would that 0.1% change save over years?