It's a different cause, but it's still the same result of "oh, so I don't have a shot with them? Fuck this", even though as a random fan they never had a shot. Basically just parasocial delusions in both cases.
No, I disagree that it's the result of "so I don't have a shot with them". Homophobia, or even harmful stereotypes don't really have much to do with wanting to fuck anyone, otherwise someone coming out as asexual/aromantic would also lose them popularity, yet I really doubt any fan would care about that. Unless you have sources that show that many of those fans really dropped them over "I can't imagine dating him anymore" and not "I can't like a gay guy, gays are weird/unmanly/sinners/woke agenda/whatever".
I was thinking that the celebrities in West have started as rebels, or at least pretend rebels - rock stars were created during sexual revolution, sex, drugs and rock'n'roll, and that made it normal for them not to be pure. Rappers had parental advisory plastered over their CDs and even pop stars were often shocking and scandalous, like Lady Gaga and her meat dress. IMHO That history made it safe for Western celebrities to not be pure, while Asian societies are more conservative, praise conformity and expect contrition and apologies for scandals, which made it possible for the whole idol purity idea to get popular and common. Imagine Kanye West shaving his head and apologizing in tears because he did something scandalous.
You can still get cancelled in West over political issues, or even non-issues that someone with no life made political on social media, but you can also weather this with your remaining fans. JK Rowling is still getting rich from Harry Potter, despite angering quite a few of her fans, and I doubt people in Japan even know about any boycotts, even though probably some Japanese Potter fans care a lot about Hermione's virginity, for example. Japan seems to either ignore the scandals, or expects apologies in dogeza, or even total blacklisting. There is also that thing where even criminal's family is treated as evil accomplices.
