I worked at a creative studio that used Linux during that time. For many periods of time there literally was no solution for doing something as trivial as watching YouTube videos (a huge need for reference) because of trying to pin down the right combination of 32/64 bit OS, browser, and Flash plugin.

Even in windows I remember flash was often a resource hog and crashed the browser regularly or would freak out and I'd have to restart it.

I had similar experiences.

Adobe had zero F*s to give about anything not mainstream.

i remember cheering apple on as they were killing flash because of how abysmal it was on linux. I do miss flash in a way, but also good fucking riddance

Well the SWF file format was (is maybe still) available and Adobe publish(ed) the spec with no strings attached.

No one wanted to do it.