I raced in the early 2000s. Power meters were expensive, but Pros had them.

The only thing back then is they sometimes didn't use them on race day for fear they were too heavy.

Bikes are actually much heavier today than they were back then. Almost all bikes were near the weight limit back then, I just read an article where they weighed riders bikes at the TdF this year and some bikes were over 18lbs.

Disc brakes + Aero + Electronic components have really made the bikes heavier and have made it much more expensive to get a bike at the same weight as 10-15 years ago. You're either spending about the same money and getting a bike that is 1.5kg heavier or you're spending 2-2.5x more money to get a bike as light as what you would have bought in 2010-2015.