What changed is the demand grew enormously and in response, as in every other business of life, a lot of people who only have passing interest in it got into it because it pays well.
So now you have companies have to sort through huge pile of mediocre candidates. This causes the process to be very noisy, a lot of screwed incentives and a lot of false positives and negatives.
Applicants are now hedging their bets and applying to multiple places means that they are unwilling to spend entire day in each one. And companies (those that do not understand how important hiring is) also have incentives to spend less effort on hiring.
And developers became much more cynical. Partly because of high demand they are aware of. Partly because companies do not treat them well (like not giving raises at a rate their potential salary is appreciating as the market and their experience changes). And partly because new generations are just much more disillusioned.
I had a person recently refuse to come to 2h interview. Apparently it was too much effort. Good riddance and thank you for saving my time.
Good news is that good developers can still easily find a good job wherever they want.
Bad news is that most people are not good developers and they don't even know about it because really good developers are so few and concentrated in relatively few places. In effect, most developers will never have a chance to work with one.