On that basis, the idea "women are socially pressured into wearing make-up" falls short. Women, themselves, are rejecting the idea.
> your clients and customers will think less of your business
This isn't all jobs, though.
A doctor, or back-end dev shouldn't feel any pressure to wear lipstick.
If you want to direct criticism at those roles/instances where there is a problem, and maybe suggest solutions, I'm fine with that, but broad strokes don't do much help.
Incidentally, I see fewer women in my own country wear as much make-up as those in America appears to do. I mentioned "doctor" specifically because I am surprised how much american doctor wear. As a further anecdote, whenever an american version of a European series is remade, the american actors are usually more attractive..
Fact of the matter is, if you employ women who don't wear makeup, your clients and customers will think less of your business. You'll lose money and some positivity associated with your brand. Your managers will think less of your female workers - so will their coworkers, no matter the official policy. This isn't the sort of thing that gets changed by a line in a policy document - this is the sort of thing that needs widespread social change.