https://imdbapi.dev/ is indeed very interesting resource, but still it looks to me with limited data?
True. There are thousands of species of fish and yet I only eat a few of them, so how would I categorize them?
As a casual user, I don't have the same data requirements as a film student.
I'm impressed by your technical acheivement in piecing together multiple programs to scrape every single byte from IMDB. I remember you from times past, from near the beginning of PVD. As a moment in time, this is a huge achievement.
Every 18 to 24 months, IMDB updates it's HTML. I'm sure this just is a refesh of the site and the introduction of new technology. The last update came about when AI became part of the site. When the next update comes, you will be the only person that can resolve the issues.
I'll say simply, "Take what's given" and build from that. The 'dev' site is simple to get data from, and for those want more, you have that solution.