This absolutely depends on the time period and location. This is not a good blanket statement to use for all of ancient greece. And even when looked down upon it was a very common occurrence anyway.
Athens had laws against adultery going as far back as Draco which is essentially since writen law was first codified at 800BC. Laws against adultery existed since the beginning of writen law. Any periods beyond that and you're into oral law. What period was adultery considered acceptable?
Which is specifically what Plato argues in the Symposium - yet, he also doesn't refute that they were lovers, and takes it for granted that they were. The symposium specifically states that in this case, Patroclus is the eromenos as a result of their hierarchical positions, rather than age.
The issue here is that greek has multiple different types of love and its not even entirely unlikely that plato (the guy who invented platonic love and has it named after him) was being vague or refering to multiple times of love.
This has happened in the past with plato, when he said that same sex lovers are blessed, making people think he was in favour, only for him to decry homosexuality as unholy, ugly and odius later in the Laws, confusing people as to what his stance on the subject was while it was clear he was talking about platonic instead of carnal love.
And this is ontop of the fact that plato openly decried both homosexuality and pederasty.
This isn't relevant. I'm not saying that it was ever explicitly stated Achilles and Patroclus had a physical relationship. Just that several passages do have very romantic connotations in their original text, and Homer did seem to very deliberately leave it open to interpretation.
The problem is that this would seemingly be the only thing left open to interpretation.
In such a massive text Homer has shown that he doesn't shy away from mentioning physcal relationships if he wants them included. He also has enough detail in the texts that we found the real life location of troy just from the illiad alone. Its a text rich in detail and explenation in every single aspect but for this one thing people just assume he left it vague on purpose/accident instead of just not including it because it just wasn't intended.
Saying that he left this one relationship vague is a very modern spin on the subject. Especially considering that every other relationship was completely explicit. Why would he leave this one thing as implied and make everything else explicit?
This can be debated, and has been, and it was a more common interpretation before his time that they were. Experts make mistakes, and there were experts before and after him that disagree. We can't defer to one singular account to prove pretty much ANYTHING. I don't know why we would here. On top of that, his main argument (that this whole segment was put into the story later) is pretty impossible to argue for or against.
Of course experts make mistakes and we can't rely on a singular account, but experts are still experts and also have a hiearchy. If the most acclaimed scholar in history argued in favour of them being lovers you would be calling me crazy for dissmising it and not accepting it as a source, because some sources are naturally more valid/trustworthy on subject matter than others. General speaking, he is regarded as the highest authority. I'd argue his word holds enough weight to be worth mentioning.
This, again, is irrelevant? I'm not getting into why the story exists or what it is meant to show. Specifically, though, within the Zeus/Ganymede myth it isn't debated whether or not Zeus was physically attracted to Ganymede. It's pretty explicitly clear. But Xenophon's interpretation is that he wasn't - and that he was simply attracted to his mind. And yes, that is absurd.
This is relevant/not abusrd because pederasty in general was considered a relationship that was of the mind as its purpose was to be educational. Erastes were supposed to nourish the minds of the Eromeni as teachers and mentors, in everything regarding athenian life, from law, to arts, to language and even sex.
Erastes, in theory, didn't select kids that they just to have sex with, they select kids to raise as proper citizens. Claiming that as an ideal it was a relationship of the mind, is not at all absurd with the cultural context at the time.
Of course today we can just obviously infer that they just wanted sex, as did many people at the time as well, those who decried pederasty, one of which was Plato, but the official justification of the subject was that this was an educational and mentally nourishing experience.
I didn't ignore either of them, and I'd measure that I'm a bit more studied into the context of these texts, actually. Greco-roman culture and classics are probably the topics I'm most studied in.
Realistically, if you have this conversation with enough people that have a strong knowledge base about the culture, I'd be willing to be the majority of them will give you the same answer: While the text isn't explicit, it does appear the two had some romantic inclination taking the translation at face value within the context of the culture at the time - and it was a common interpretation to view it as such. You don't have to take my word at face value. The internet has several places with people who are more educated on this than you or I, and it's also possible to reach out to experts in these fields.
You say If I have this conversation with enough people/experts on the culture, they'll reach the same conclusion.
How many Greek scholars that have studied this text in their native language have you actually spoken to? I'm not approaching this subject as an english speaker who learned about the Illiad from the internet.
I'm approaching this subject as a Greek person, raised in Greece, that studied this subject in Lyceum and Gymnasium from Greek PhDs on literature that read and write ancient Greek for a living. Did the research for this change actually involve any Greek Philologists or was it just internet experts?