You are overlooking the main point of the original post.

The comparism with the old Dynamis and gil spent on that isn't exactly good, because not every group had people split the glass cost, but the leader paid it himself and got the currency in return. Others were there for their relic items, no gil involved aside from reraise items or medicines or whatever you had to bring. This glass gil also went to a goblin NPC, not to people or possible RMT selling Voiddust.

If you have time, or have the sole purpose of making gil, Voiddust is a reliable source of income right now. That's not the best way to make gil, and generally it's not a bad thing either as some people don't have many other ways of making gil at all(aside from the obvious turning cruor/ops points into gil). On the other hand though, this is pretty much what RMT were waiting for. I'm not going to say it's cause of this, but lately there have been many RMT trains leveling up again.

To say it's not the DEVs problem that we are spamming Voidwatch because of complete crap drop rates is stupid, and you know it is. Who are we to blame for those drop rates in your opinion, then? The players who do the event hoping to get a drop? I don't think so.

The drop system in Voidwatch is flawed in so many ways it would take forever to list all of them. The way Voidstones are working right now is inviting RMT to come back to the game, and they have partly returned already. Campaign, Besieged, events with Conquest Points all were not very important events in the past year or more, so they can't expect us to have stocked up on points for Dust either. Abyssea was clearly the main focus then. If they won't change the loot system in Voidwatch, why not simply add an option to purchase Voiddust with cruor? Make it more expensive than 2k or 3k, be it 5k or 10k it doesn't matter.
I'm fairly sure doing so would make less people buy Voiddust directly from the AH, and therefor make Voiddust more or less pointless to farm for gil as it will sell a lot slower than it does now. As a result, it will be less attractive for RMT as well, and they won't fully return / stop bothering again.