I have no interest in comparing this game's total players to other games' total player. But to say that this game is somehow dying or has nobody playing is wrong.

Of course, SE's revenue from this game has continued to increase while other parts of their company has declined. Lucky Bancho's statistics show that we have hundred of thousands more active players than during the same patch timeframe in Shadowbringers and this is well over a year after it went viral among streamers and a year after Endwalker release.

Concurrent players is different because it means the number of people who are logged in at any given moment rather than how many login over a period of time (such as a month). Obviously, it's highest in the evening, at weekends and after a patch.

For this game, concurrent is not relevant to any part of the debate except how easy it is to find people to play with. Most of the time, it's easy to do that except on the new data centers or when people are sleeping but it's always been like that. It's not relevant because the game is designed to be casual and allow people to login for 20 minutes to do a roulette or a seasonal event and then logout. It's not designed to hold most people in a raid for 4-8 hours or to pressure them to grind all day except for people who inflict that on themselves with achievement and item collecting.