Often when people talk about fetishes, I mentally replace 'fetish' with 'sexual orientation.'
Not cause orientation is a fetish really, but cause the contrast makes it very clear how much we trivialize and judge fetishes.
For example:
"Life is too rich to just be stuck on being straight"
"Something's wrong with you if you can't get off to straight porn"
"If you unravel your trauma, you'll stop being gay"
This sounds absurd to us, cause we recognize orientation as an immutable, fine part of self.
But a lot of fetishes are like this too! Some experience them in the exact same way as orientation. I often hear stuff like
"I always remember being into x, even as a child"
"Sexual stuff without x just doesn't arouse me"
"When I did x I finally felt like a normal sexual being"
I know one person who spent their whole life trying to be "normal" sexually, and then when they finally started engaging with the fetish they reported "I'd felt like something was wrong with me, but now the way everyone else has been talking about sex is starting to make sense."
I don't know how 'orientation' or 'fetishes' interact, I know they don't overlap fully, but at this point I treat many fetishes as basically subcategories of sexual orientation - and I respect them as such. We shouldn't shame fetishes much like we shouldn't shame being gay.
I think the main difference is that we don't actually frame sexual orientations as being explicitly sexual, but focus on relationships, whereas fetishes are explicitly sexual.
I agree somewhat, but want to point out that some fetishes blur the line into relationship/lifestyle; 24/7 bdsm relationships, for example, are pretty relationship-focused.
True, but such fetishised relationships still present in a way that is more explicitly sexual (generally taboo) and/or have more legitimate reasons to be viewed with suspicion.