Stop looking at TheTVDB.com. If MC identifies a file as a movie, which it assumes if the files is longer than an hour, it looks it up on TheMovieDB.org.
TheMovieDB.org lists three movies with the name including "Color Out of Space", two with a prefix of "The". The most likely issue with the automatic Cover Art lookup is that MC receives a response of three movies, can't pick which one is correct, and so doesn't download Cover Art from any, as it may get it wrong. I believe I have mentioned this before, with examples you have provided.
If you are doing this testing, you will only get relevant results when you are importing a file for the first time ever. If you try the same file again a second time, MC already knows about it, and that changes its behaviour. If you wish to test with the same file over and over, you need to delete it from the MC Library, and then delete it from the MC "Removed Database".
Anyway, all of this was covered in your last thread. Maybe your files are being flagged as TV Shows instead of Movies. Maybe internal tags are responsible for that. Maybe because you are importing recent movies mostly, the online databases aren't up to date. The last thread left us both stumped. Your use of Radarr does add another variable into the mix that others don't have. Maybe it is flagging the files as TV Shows.