I've been seeing a lot of false narratives about Supergirl recently so let me tell you the real reason it bombed

No it wasn't because it came out before minons (lmao) or because it didn't stick to the comic 100%. The number one reason this bombed is because it was a blockbuster budget that only appealed to a tiny niche audience.

This story (and this version of supergirl overall) does nothing to interest the typical male super hero demographic at best and actively turns them off at worst. It was too edgy with sexual enslavement themes for young girls and families. So it basically landed only with 18-30 year old women who were already into superheroes or liked the edgy girl persona. That group seems to like it but that's a very small audience in for a 170m budget.