Final Fantasy XII came at a weird time where the next gen was on the horizon, and it had to come out after FF10 which introduced a whole new generation of players to final fantasy, and in which its main hook was a specific brand of discount, anime-like melodrama about love and the power of friendship. FF12 on the other hand tried to go back at a more "classic" brand of Final Fantasy that is more focused on geopolitics and believable human interactions (see: FF6, 7, 9), but with the veneer of Matsuno that makes it closer to FFT. The issue is that the vast majority of people who likes FFT is nothing compared to the vast audience for mainline FF. So inserting Matsuno's brand into the mainline series is like telling people to enjoy a 10-part hardcore fantasy book series when the only thing they're used to read is the Harry Potter book series. Just look at the amount of people getting into a fit just thinking about how there always was politics in their video games. People doesn't want to think about social classes, oppression and racism. They want escapism. Vaan is super hated even though he is the character that cements the kind of world they're in, and the discrimination they face from the Empire. Most people doesn't want to do with any of that shit.
Furthermore, Final Fantasy XII's lack of hand-holding and heavy use of foreshadowing is one that trusts the player to pay attention and take the time to soak up the world around them. Take FF10 again, you could skip any discussion with any NPC and still understand everything fine, they are for the most part irrelevant. This is not the case with 12, which is also something that works against him as it does borrow from classic western RPGs on that front. NPCs have a lot to say, and they offer new dialogue after most story events. But, no one cares about doing this except for the people who are dedicated.
The game was clearly ahead of its time, if only to see that other popular games like Dragon Age have been influenced by its battle system (and WRPG being inspired by JRPGs isn't common
at all). It was never surpassed either in many areas, as the depth of the gameplay has never been matched in the Final Fantasy series since then. It might even be the very best gameplay system Final Fantasy has to offer alongside FFT and FF5. Its wealth of options allows you to do anything you want, in the way you want, with a lot of room for experimentation. Not to mention characters expresses a lot of personality through it too, as they ALL have 2 or more animations for *every* weapon types and there is a boatload of weapon types in this game. It offers a playstyle for everyone because the gameplay system is also not railroaded. You choose the battle speed, the gambits to put, whether or not the game pauses when you choose actions, and then you can get in the very granular : the charge time of every weapon, what character is faster with this weapon type, what spell should I use in what weather, changing weapons when the weather is windy as that affects accuracy, and so forth. It just never ends, and it's a great thing for people who wants an involving gameplay system that *remains* involving through the end. Again, very different from what came before with FF10, and the end-game doesn't consist of spamming quick hit to victory either. This is also why I roll my eyes when people keeps repeating the same "it plays itself" meme.
If you willingly spend time to go through the effort to be on full automation, to then complain about it, then this is my answer
And I think during these 13 years, it's very clear that "freedom" is not something that is sought among a subset of the Final Fantasy fanbase, which shouldn't be surprising at all, but it needs to be said. That I see so many people working against their enjoyment is a bit baffling, and understanding the reception of FF12 is also understanding why JRPGs are working hard to remove that agency, and only offer the illusion that you have it. A lot of people simply doesn't want to be free to do what they want.
So would it be better received ? I mean FF12 was a critical darling during its release. And the 2017 release shows that it is still the same behemoth as it was before. There is also a very clear shift in opinion, you wouldn't have found the same amount of praise back in the old forum in a similar thread. I'd say FF12 improves as time goes on, because it offered a direction of the genre that becomes more and more interesting to look back on, and it's becoming even more relevant as other mainstream JRPGs are simply not able to match in terms of "relevant" content, as opposed to the sheer amount of uninteresting time-wasters you're provided in other games. FF12 was a JRPG with a real amount of 50 hours of tangible content, that's not something you would see often in the same space. And at the end of the day, you're still getting Ivalice, the best universe the FF series had to offer, the incredible music by Sakimoto (which was so maligned back then, it was ridiculous to see the amount of people who couldn't get over the lack of Uematsu), and some of the best art design in the genre (Rabanastre, Bhujherba).