No, it is not a wipe and restart. Although it would be a ‘fair’ way of rebalancing everything, that would only drive at least 75% of the remaining players away and the number of returning players would not be nearly enough. This is a released game, and most players (unlike those of us who participated during testing phases of the game) do not really like redoing content they have already done.
That said, there has been irrevocable imbalances created due to past and current issues. You acknowledge this wholeheartedly when you found out what happened when some people got lots of gold. You couldn’t just remove the gold or items purchased, entire markets were purged and people maxed out their skills. Your solution was a rollback. That means you acknowledge the damage done when some people had a huge advantage. Just because it wasn’t as obvious with the earlier issues, doesn’t mean this same thing didn’t occur at a lower level before. 1-day bans without character rollbacks resulted in the same problem; people getting skills maxed, HWM maxed, and all the trophies by exploiting your game. Your stats showed people getting to this point and to prevent the majority of non-exploiters from doing this you nerfed all of those avenues so you effectively punished non-exploiters while benefiting exploiters. That is the reason many people have left and or leaving, even if they don’t consciously realize it.
My suggestion would be to, in a single mega update:
(1) Set everyone’s skills to 200
(2) Set everyone’s HWM to 600
(3) Set everyone’s gold to 10k or something
(4) Give everyone 3x major trophies
(5) Implement an actual combat balance change, not a massive imbalance change
(6) Increase skill cap to 300
(7) Add 650 or 700 GS items to the game (gear did use to go up this high before)
(8) Rebalance your luck system (gathering / general) so the given trophies give you access to the mats/item drops that currently exist in the game, but generally require next tier trophies/skills and HWM to get mats/drops for higher level gear and drops.
TLDR: Fix broken things, effectively reset the game without having players regrind existing content, and add content to keep them playing. I think this is the only way you would bring back any sizeable portion of the population that left.