People really gotta get off this PSO3 delusion.
Just cause you got issues with the game, like we all do, doesn't mean Sega is going to abandon such a super profitable game to start the sequel out of nowhere.

Not just that next year there is a Western release that is likely to be really popular cause so many people were waiting for it and cause it has the same content as the Japanese version (even if we don't know what's gonna happen to collabs).

PSO2 is not just getting ever more popular but also improving all the time since Sega actually listens to players (even if they get confused / pick the easy way out at times like not shortening the time it takes to use shift pas on phantom but rather making markers easier to see) and if they dropped one big texture pack to upgrade the game to at the time current graphics they can do it again when tier 6 becomes outdated.

So in short there is no reason whatsoever for Sega to even think about a sequel to this popular and profitable game but instead focus entirely on making PSO2 as good and popular as they can till at least the planned 10 episodes are done but even then it's possible the game will receive more content if it's still popular enough.