I feel that they are still raw over PSU so that is why they are dragging their feet on how they want to release in NA. Mircrosoft may have dumped a crap-ton of money to get it over here, but its obvious JP was happy with the way things were, the money may have been needed to fund another product so they caved, who knows. We also don't know if JP has any data or forecast as to how well they assume PSO2 will do here. The (lack of) effort SEGA is putting to advertising and promotion is very telling to me.
WE may be fans and love this game dearly, but JRPGs and their like, unless it is a very will established franchise (I mean like, ZELDA, Pokemon or Final Fantasy established) they don't do well here. Even with the second Anime Renaissance happening games like this are considered niche in a sea of realistic combat sims. Phantasy Star is a beautiful world and lore rich but has always been marketed poorly. We haven't had a worthy successor for PS4 in decades either, so the knowledge and hype about the franchise isn't something that is in the mainstream consciousness, but JP wants to treat it like it is because in JP it is.
I personally think it will do fine, it will taper off, flatline and if they keep expanding platforms eventually will be a nice little cash cow for them. There are plenty of lesser MMOs in the same vein that are not in maintenance mode and doing just fine. I just wish SEGA would show a bit more enthusiasm so we could get the word out easier, as it is it just feels like it is all up to us to try to get more players on board. That is had when a publisher seems a bit low-energy about the whole deal.
(None of what I have said is to be considered fact, they are opinion. There is no evidence or proof of anything I have said. This is just observation and interpreting what I have seen so far. If you disagree that is okay, I will not claim you feelings are invalid. Love and peace.)