And generating those tools was easier when you can pay people to work full time on it; open source doesn't pay nearly as well if at all.

but making them easy enough for mass adoption

In the attention economy, making them easy enough translates to making them addictive enough. I've been using a dumbphone for four years and every time someone asks about it, they say something like "I wish I could do that."

The thing people want is also what they hate.

And they did that because of loads of funding from those who understood the geopolitical power that comes from these tools and a willingness to accept massive spending and financial losses for decades, that normal investors wouldn't touch, e.g. The US government. DARPA, NSF, DOD... funding

E.g. The Internet, Google, Apple, Tesla etc...