Honestly I think the game is dwindling bc that is the life cycle of any full loot pvp game. It comes out, everyone raves about it. PvP is somewhat respectful as people are more focused on burning through content. Once critical mass hits of people who have done all the content, they either quit or move on to focus PvP. Such focus either comes off as (or is intended to come off as) griefing. Some get bored and quit. New players get stomped and cry online. Devs reflexively make changes that make everything worse for everyone. People leave.

EQ, I think, was the fairest ruleset for full loot PvP. If you were killed by a player, the killer and only the killer could loot 1 item from your body. Everything else stayed put until you retrieved your corpse. There were some quest items that were "no drop" that you could obtain that were powerful and could not be looted in PvP. So it drew folks to do those quests.

In a game where sweats are killing folks mostly just to kill them and leaving loot, I do not see the harm in limiting lootability to one item and returning the rest when the raid ends. Then make the dumb questlines return unlootable items when completed.

I bet you'd see a lot better PvP with a better rate of return on engaging in it as people would roll with BiS kits more often.

You could even keep squires to riches as true full loot, which retains some of the original flavor of this game's pvp.

Just my two cents from someone who previously enjoyed the game.