>>31142244There are completely viable ways to rotate pokemon and movesets out of the competitive meta without making regular players unable to use the pokemon they like. Use the damn generation-indicating iconography like the kalos pentagon and the alola cross properly. Stop making every legendary available in every generation. It is completely within their power to just never give away a single genie with the gen 7 cross, and in gen 8, never a single ultra beast with whatever check those games have. You could still transfer them and play with them, but not in OFFICIAL tournaments because that's not this "season".
Rather than deleting the old icon when they get brought forward to a new gen, let them keep their old icon so they can be kept compatible with throwback formats and seasons to previous generations. Injectors can obviously just create Pokemon with these icons that shouldn't have them, but then you're getting into injecting illegal Pokemon outright.
Rebalance learnsets and TM compatibility in a generation so certain widespread moves that shouldn't be widespread no longer are, or vice versa. Ice Beam doesn't need to be a TM. Making every water-type in the world not able to get it for free would be a start towards improving ice-types. You can still transfer your old Pokemon that learned those moves in older games, maybe even use the fact that they've retained their old icon as a compatibility check that still lets you use that TM on them even if a newly bred one couldn't. But competition legal Pokemon won't be compatible and will have different moves available to them.