I know it seems like it but I am not really missing your point.
"By your perspective, people of the future may think us immortal for eating meat, supporting capitalism, and assuming genders."
The key word here is "think." Put in the most simplest terms, subjective morality is a very fancy way to say "his/her opinion." Their opinion is void of any reason and universal checks and balances, so because it fails that morality test, it never actually is a moral statement.
"Just because a future perspective may overrule a moral majority doesn't negate the morality of those previously."
If morality is subjective and determined by the majority, sure. But it is not so there are objective ways to look back at history and say who was and was not morally "behaving." And there is no such thing as a "moral majority." That's is just a fancy way of saying mob rule.
"If these become the new standards of morality, which I hope they do not, then you'll be subjected to their judgement."
Calling an opinion a moral standard does not make it an actual moral stance, thus, them subjecting me to their "judgement" is not the equivalence of being judged on a moral ground, it's more like a bunch of kids having a bad opinion of me.
"If morality can change, then it is subjective."
Again, my point is it does not. People simply take their opinion and slap a "It's my morals and my truth" on it and think that makes it a moral, when it does not. I can slap a Lexus sticker on my Camry and called it a Lexus, the observable truth would still say the same: It is a Camry. So no, morality cannot change, just people mislabeling morality and their opinions.
"Anything intangible is subjective and that includes morality."
The premise is not true because intangible scenarios can still provide objectivity. I would challenge you to provide me with an intangible scenario that we can not reason through or construct objective principles from.
"Sure, you can assign tangibility to morality but that doesn't mean it's not subjective."
Care to provide an example of assigning tangibility to morality? Because morality is actually what is intangible and the observable results of good and bad morality is the tangible results. So morality exist in the intangible as the actual rule and morality exists in the tangible as the results of that rule.
BTW, I just want to say, I am really enjoying talking to you. You have remained very civil and you seem incredibly genuine. IOW, you stand out so thanks!