I think the opposite is true, actually.
Homophobia is this complex, weird, cultural thing that varies like incredibly widely, and is incredibly culturally-specific. Like there’s no “universal” homophobia. A culture can be super-fucking-macho and male-supremacist, for example, and be quite positive or neutral about homosexuality, or equally, it can make it a death-penalty crime (though there’s a complex discussion about how much, historically, that was enforced - and then there’s an even more complex discussion on what pre-Enlightenment cultures thought the death penalty was for - in many cases it seems to have been spiritual redemption weirdly enough). Sometimes it’s just bizarre, like with Rome, where a Roman citizen who was a bottom was seen as a criminal, but if they were a top, it’s just “men being men, who cares”, and non-citizens were not seen as criminals if they were bottoms, but maybe were if they were tops. I wish I was making this up lol but it’s for real (though it is even more complicated).
Whereas not being homophobic is a lot simpler and requires essentially no justification, because you’re just not doing a specific cultural thing.
Same-sex unions (which are often not called out as homosexual, but would definitely work out really well if you were) or even outright marriages are all over the place in history too - https://en.wikipedia.org/wiki/History_of_same-sex_unions
The big problem is that most of the history that’s “popular” is filtered through deeply conservative/oppressive cultures, whether it’s the Victorians (and even Tories into the 1990s for god’s sake) here, or the Chinese government in China, or wherever, groups which were strongly interested in suppressing the FUCK out of information about this sort of stuff, or wildly creative interpretations of stuff to say it “wasn’t gay”, often engaging in the classic canard of “Just because two men love each other doesn’t make it gay!”. Sure, it doesn’t. But when they sleep in the same bed, live in the same house, show no interest in the opposite sex and so on, in an era when admitting you were gay would get you imprisoned or even maimed or killed, then I think we’re into shenanigans territory to try to claim they weren’t.
You still see this, with lunatic claims like the Michelangelo or other figures with well-recorded or even outright professed homosexuality “weren’t homosexual”. Usually the lunatic is a 50+ man of a conservative bent of course. I mean, jeez, just in that article you can see that gay marriage in Rome was common enough that angry Christians (sigh, thanks for ruining everything guys) made it illegal in 342 AD (specifically they call out actually getting married to a man, as a man, as the problem). But could you have learned that easily in 1990, say? Fuck no. Could you have learned that at all in say, 1960? Not unless you were an actual historian.