I’m definitely not going to trash unions, big Billy Bragg fan here, but mentorship and training of less senior people is already basically table stakes expectation for staff+ engineers at any competent tech company.

I actually think it’s overemphasized on the internet, if anything. Staff+ engineers should still edit (I don’t say “write” because “delete” is even better) code. Otherwise what’s all the training for? Getting the senior- engineers up to “mentoring” roles, to train even more senior- engineers, …?