HR protects the company, not the employee. That's just a fact. When company culture is great, that can be fine, but when it's bad, it absolutely sucks. When there's a culture of misogyny and sexual harassment, HR helps to cover it up to "protect" the company, and it's awful to see.
All jokes aside, if these allegations are validated by an external source, heads have to roll. A slap on the wrist is disheartening to everyone who may have been belittled and goes further to discourage interest and diversity in tech.
I have worked in IT R&D for a decade, and this is something I have had to address multiple times with my team. Everything from sexually charged comments to just general patronizing. The key is that you can't let something slip through or that's the new standard. You have to address it quickly, in the moment, and be decisive about what is acceptable and what is not.