Software developer salaries went up significantly after 2016 and it was a super hot market for developers in 2020. So whatever you saw wasn’t a good indicator.
It was very much bimodal. If you were working in BigTech or adjacent, that was definitely true. If you were working in enterprise dev like most of the 2.5 million+ developers working in a tier 2 city outside of the west coast in the US, comp was definitely stagnating.
In 2016, I saw the writing on the wall and knew I had to do something when my (step)son graduated in 2020 and my wife was willing to move anywhere the money took us.
It just so happened that a job fell into my lap at AWS working (full time) in the consulting department. I am no longer there. I now work at a third party consulting firm as a staff consultant specializing in app dev.
Yeah someone joining a good company as a senior engineer in 2015 would retire with about 15M in assets now assuming smart investments (say... half on big tech stocks, half in market indices)
Someone joining now on the other hand, might have to resort to physical work at some point in the next ten years of things go south.
It's easier to lower standards than to raise them.
There's always a race to the bottom. I don't think it's a big leap to suggest that what's considered the "minimum viable product" has decreased over the years. It's also no secret that software is getting worse.
As to salaries, I think you forgot how things worked before. The reason companies like Google introduced free food and all the incentives was because increasing salaries was not a better way to attract better talent, since salaries were already high. So either now something has changed where better talent cares more about money or we're attracting talent that cares more about money. As in either the same people changed or we're attracting a different type of person. Personally, regardless of age, regardless of field, I've seen a strong correlation with the best people not caring as much about money. Once the salary is good then they care more about how interesting the work is or how they can reduce stress in their life. Money matters, but it has decreasing utility as it grows.