The biggest issue for changing percentages like that, is that fundamentally the actual mindset/work required to do software engineering effectively kinda sucks.
And often conflicts heavily with the type of life most groups/people want to live, and the type of work most people want to do.
Especially historically under represented groups.
It doesn’t mean people in any of those groups can’t or won’t be able to do it well.
But it does mean, statistically, is there won’t be a lot of them (from a sheer numbers perspective), and if you want a lot of them you’ll need to actively fight significant cultural and personal tendencies for a long period of time.
Especially since experienced people take decades to train, and are the result of massive amounts of filtering. Probably not 1 in 200 or fewer new hires will ever end up as an experienced Staff Eng, 1 in 500 as a Senior staff Eng, etc.
If you’re a large company, that means you have a huge pipeline problem, if for instance, you need to hit some target number of people with some coarse criteria of color/race/gender/sex, whatever.
Because there probably just literally aren’t that many that meet any other criteria you would use. Either because they got filtered out due to some discrimination thing too early on, so never had time to grow to the level you need, or just went ‘meh’ and chose some other different path.
But for many years now, the DOL in the US has been requiring large companies to hit mandatory percentages meeting those coarse criteria. For some criteria, decades, but for most less than an decade. And have been enforcing it.
So 1) you can only move the needle so far, before every potentially plausible recruit could be hired, if you try to do it right now, and 2) in many cases, the issue is the groups involved just flat out don’t want to do/be that thing enough, for a ton of reasons.
One big issue in California in the Latino and Black communities for instance, is investing in schooling is seen as a serious ‘nerd’/uncool thing, same with professional employment. So both those communities have huge issues with grades and education. There are also historic issues with ‘the man’ smacking down members of those groups if they try.
East Asians (and US Indians) see education as a competitive necessity, and professional employment as a measure of success - the classic ‘Asian Parents’ trope is very real. They have had issues with ‘the man’, but have managed to mostly sidestep them, and are very highly represented in education and professional employment. To the point they have been actively penalized in many Affirmative Action programs.
If it takes one woman 9 months to make a baby, you can’t get 10 babies with 10 women in 1 month. Even more so when 9 of them are on birth control.