It it some kind of hedging strategy by The Pokémon Company to account for the number of different streaming services (thereby actually making the problem worse)? Was there some kind of timed exclusivity deal that's forced them to put different things in different places? Did one of the streaming services come along at a later time to try to undercut the earlier ones but the earlier licencing deals haven't expired? Anything else?
So each service buys a single season to tick that box.
E.g. Annexe.txt (that you might assume would be safely opened by a text editor) could actually be Ann\u202Etxt.exe, a dangerous executable.