No, the total number of unique players is not the sum of all players in the various formats. If you take another look at the table, you'll see that the sum is much more than 15,000 counts, but the total is 8,967. Players are only counted once at a time, no matter how many battle formats they appear in. The number of players who participated in Season 163 is actually 8,967, according to the battle logs.
We currently have approximately 13,700 registered players in our logs since June 3, 2025, which means that about 65% of our active registered players participated in Season 163.
Thanks for stopping by and commenting. By the way, sorry for the initial downvote; my mouse was running out of battery and was doing whatever it wanted.