A couple YouTube tabs are enough if you leave them running for long enough. Just one YT browser process will easily take up 1-4GB sooner or later.

While I agree with your statement, I don't think judging one's way of working and using their computer was necessary.

I could have two browser windows open in the late 1990s. I have about a thousand times as much RAM now. So even with 10x more bloat in the pages, I should be able to open 200 tabs just fine.