Maybe on your data center's Discords. Not on Crystal. We only relay when the train is ready to start and give people about 4-5 minutes to arrive before first pull. We've got one world that runs trains on a set schedule; the other worlds run whenever someone feels like doing it (assuming the marks are up).
It's unlikely that data center travel will have much impact on trains considering how frequently trains can be run (only once every 6 hours per world assuming there has been no free hunting happening in the meantime). Running to another data center for a train will likely mean you're missing out on the train that's happening on your own data center. Why would you bother going to another data center in that case?
It will have even less impact on S ranks. By the time you log out, select the data center, wait for your information to get transferred, log back in and get to the location, it will be dead.
Rank As were definitely intended to be done by small groups. A skilled tank has been capable of soloing them all along (though you need Nari at certain spawn points to solo).
It's the S that are intended for larger groups.
The achievements were there for those chose to make hunting their primary end game and had lots of time to do it. Players were getting them even before trains became popular. Trains have only made it easier to get those achievements and cross world trains have made it even more so.
Exactly. Hard enough when you're just trying to use world visit. Not going to happen via data center travel.
A 5 minute invuln window isn't going to change anything. People are still going to complain they're missing out.
Players were never intended to be able to get to every kill. That's what a part of the community keeps failing to understand. If SE wanted the entire community to be able to get to the kills, the system would have been designed differently.
Keep in mind that what we're experiencing now is not going to be what we're experiencing with Endwalker hunts when Endwalker releases. There won't huge numbers of players at level cap for several weeks. The gear most players have will be the equivalent of the Ronkan gear at the start of Shadowbringer instead of far more powerful end of expansion end game gear. Things will be dying more slowly.