I think the bigger issue isn't that RMT exists, though it would be nice if it were minimized (realistically it will never go away completely), it's that the supply of items in the game hasn't kept up with the demand of more players hitting high levels, and that almost anything can be bought for enough gil, including EX items off HNMs.
SE has made a lot of good steps in making the lower level items like Leaping Boots, Emperor Hairpin, and Peacock Charm available in EX form or through BCs, but it still hasn't done that with a lot of the higher level items.
Some examples:
-3King Abjurations and the majority of cursed materials (let's assume most rare synth items still come off of HNMs and not from BCNMs) are still available at the same rate they were when they first came out, meanwhile not only are old players leveling up new jobs to 75, but new players are hitting 75 as well.
-CoP had very little expansion when it came to creating new supplies for items. There aren't nearly as many "major" HNMs in CoP as there were with Zilart, and definitely not as many minor HNMs as compared with the tons and tons you find in Zilart areas. If sea were much more similar to sky (100% pop item drops and synth item drops from each Jailer), I think you'd see at least a little more easing of price inflation.
-Seven very good items are still locked up in an unrealistic HNM encounter, including a replacement to Speed Belt which still comes off of a LV55 NM. A lot of CoP items in general have a very large time investment compared to Zilart items and usually aren't any better.
The good news is that SE did get some things right through new BCNMs, ENMs, Limbus, etc. I think the Limbus model is possibly the best I've seen in a long time, because it combines 3 aspects of loot (AF upgrades, currency purchases of completely new items, and 2 sets of HNM gear) in one activity that everyone can participate in. Sure, people can RMT ancient currency if they want, but it doesn't prevent other people from getting enough to get items on their own.
The bad news is that SE is afraid of mudflation to the point that they're very reluctant to add better gear for high level players, which as we saw from CoP just meant that players would keep crowding around the old content without focusing as much on the new content.
Hopefully, if Assault and Beseiged are structured like Limbus where there are multiple ways to earn items, and those items are worth putting the time in as opposed to existing items, the game will move in a positive direction and the problems of inflation and RMT will go down as people can go out and get their own items more easily. If not, oh well.
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