It does seem like time to revisit this old part of the game, because it's clear people still do want the achievements. Back when the idea of thief maps was conceived, I don't think SE math wizards considered with empathy how long the achievements for thief map clears would take, and now 5 years after the maps were introduced there are perilously few people who have gotten them because of the brutal RNG. So, it's time tested and it looks like there should be a change.

Nothing in the game should take half a decade to complete, so making the maps more accessible would be the most direct way to help with this. Adding to the suggestions on how to do that, thief maps buyable with allied or centurio seals could be a thing, or do some lore tie-in by making them available in Thavnair somehow.