I think it's fine to keep discussing pros and cons for a while, but action would be a logical and necessary next step towards either compromise or making a decision. This is what I propose (feel free to comment on whether you like or dislike this proposal or how it could be changed to be more effective):
While I know no one likes to be forced to do anything, compromise requires sacrifice on both sides. I think we should all give our word and agree to test run both discord and blab. I propose we spend a week where everyone on blab agrees to use discord as if it were the main chat for elements the game. We would discuss elements, ask questions, roll dice, coordinate league games, and even run a weekly tournament on discord. Obviously some people could stay in blab in case new players happen upon the chat, but for the most part everyone would agree that if they want to chat about something, they will use discord. In preparation for this, Discord channel for elements would be set up as if the move was happening. This means that subchannels will be reorganized in the way that several people discussed, bots would be optimized as best as possible, some useless bots would be removed, and unnecessary subchannels would be combined or removed.
During this time, everyone would look at Discord objectively, trying to see if they would be OKAY with using Discord and looking at the situation as if blab had never existed. I know ultimately it is a comparison, but actively looking for things to compare brings a lot of bias into the situation.
After this, I propose that we spend the next week using blab exclusively, with heavy Discord users agreeing to return to blab. During this time, they can see if blab is really as outdated as they think, or if they forgot what blab was like with a large active daily community. Again, people would try to be as objective as they can, being honest about features that blab has that are beneficial (or could be seen as beneficial).
I know a lot of blab users already use Discord and likewise Discord users have probably spent years using blab already. But this is more to test what it's like when the ENTIRE community is using just the one chat. If everyone goes into this biased and looking for things to complain about then it won't be useful. However, if people are willing to give the other platform a chance, I think this will provide us with more information to make a better informed decision about whether to fully move to Discord or not.