Completely agree, I've actually gotten into arguments with people who legitimately believe that parallel universes are real and supported by scientific evidence, and then they cite a bunch of theoretical articles that are only supported by more theories.

There's an entire pseudoscience subculture built around theories like parallel worlds, time travel, higher dimensions, simulation theory, etc. Literally just things that science fiction writers made up from their imaginations but because of decades of pointless theoretical "research" and theories built upon more theories people are now convinced they are real.

The best way to advanced human knowledge and understanding of the universe is to observe and study the universe, pulling a fantastical theory out of nowhere and then spending decades trying to prove its existence is backwards and futile.