Why dont they make movies from tv shows anymore?

I remember alot of different tv shows would have a big high stakes adventure in a movie and i always loved them. It allows us to see these characters in a more complete story and something we cant really do in the tv show. Its always so much fun to go on an hour and a half or two hour movie. Double episodes dont really count bc they still just feel like episodes but real movies where the story is more complex and full and its written as a movie and not a show? Thats when its fun because we are so used to seeing it in a tv show structure its nice to see how it would work with one off stories in a movie form. Even if they dont mention it much afterwards in the show i think its really fun.