The internet was slowly wrecking theaters too and COVID has just finished them off.

Well you're half right about that. The internet wasn't killing theaters prior to 2020. The last decade saw an explosion of billion dollar titles and averaged 10-11 billion in yearly takes.

8 movies took in over a billion at the box office in 2019 alone.

Covid killed everything. Studios putting their titles on streaming is the factor that changes everything. Before, you get piss poor camrips of people in Brazil or China pointing a hidden cam at the screen and upload em to stream sites. Those usually got 2.5-3 million views in the first week.

Now you get pristine quality 4k streams uploaded the same day as the movie's release. It's not a surprise to see m4u, putlocker, and torrents in total averaging 8 million hits/downloads in the first day alone. No incentive to go to theaters or pay for streaming services when you can torrent/stream everything for free now.