Right. But that doesn't mean the performance of Flash was bad for what it was doing. Or that it was worse than the performance of doing the same thing in modern HTML+CSS now.
You remembering a few optimised instances does not change the reality that Flash was bad.
Of course modern computers are orders of magnitude more powerful! But Flash was definitely generally worse compared on the same hardware and network stack compared to vanilla (non-plugin based) web tech.
I feel like people are talking past each other a bit here. FlashScript was never very fast, and rendering a document as a giant collection of bezier curves was not fast, but the people doing animations with it were getting the equivalent of modern day CSS3 animations + SVG, and it ran nicely on hardware two orders of magnitude slower than what we need for CSS3+SVG