I think a lot of companies do care about diversity, if only because research has shown more diverse teams tend to be higher performing, and companies with more women in the c-suite and on the board tend to be more profitable than the ones with fewer or none.
However, it seems to fail to get through to all levels; HR is on board, all directors and higher have had diversity training, are aware of unconscious bias and so on. But a lot of the recruiting, while it goes through HR and so on, the actual decisions and interviewing is done by people lower than director-level, and they haven't had the diversity training (because there hasn't been the budget to roll it out to lower levels yet), and they are worried about "team fit", and so they are more biased towards white middle-class men like them.
Obviously NAMALT (managers, rather than men), but enough of them are that it means there is no pipeline, and there is not a critical mass of women that makes it seem normal to have them there.
Plus, they don't see the diversity problem ("well, you're here, so we do employ women, don't we?") and don't think it's anything to do with them. Whereas I don't know of a single woman working in IT who hasn't at least considered how they are seen as a role model, whether they should be actively involved in STEM promotion and so on - I do sometimes feel bitter that that sort of thing just doesn't even feature on the radar of my male colleagues.
And I'm not sure what to do about it - I'm active in promoting STEM careers to schoolchildren, and I witter on about it enough here, but I don't seem to be able to communicate it to my immediate colleagues, even though they see me going to meetings, organising stuff, trying to get them to sign up and so on. But they still don't seem to get it. Women just don't want to do it. (I don't think I'll be able to get away with doing a course on Feminism 101.) Don't see the problem, doesn't interest them. And it's not just this company, I've seen it at others.
Also, when it comes down to jobs - a lot of our vacancies at the moment are sales and marketing types. You can't employ more women in tech if you're not recruiting in tech departments. Although there do seem to be more jobs around more generally at the moment, so that's not necessarily the story everywhere.