Except it's a rare player with strong social circles that isn't also using Discord or a similar app these days. Even if I'm on the same world, I'm far more likely to be talking with them in Discord than using a game channel.
I haven't had to play content solo yet except by my personal choice. Queue wait times for me on Dynamis have generally been about the same as they were on Crystal, maybe a minute or two longer. It hasn't been a hardship. I know PvP is different (I don't PvP to know from personal experience) but otherwise I'm not hearing complaints from anyone in game.
SE already explained why cross DC queues are not currently possible. They didn't say it would never be possible but they made it clear that it's not something players can expect to see happen in the foreseeable future.
If we chose to transfer to Dynamis, then it's on us to work to build a community that others want to be part of. If all you do is spend your time on other worlds, was it really worth transferring to Dynamis just to say you own a house you never use because you're never on your home world to use it?