>>21754432Because the thing is that singles is fundamentally different than doubles. In doubles you have a lot of work arounds for overpowered pokemon like taunt, follow me, protect etc.
In singles, over powered things often have no counters. They often have a handful of checks that are mutually exclusive to the different set variations they commonly run. Mega Lucario was like this. It ran 4 common sets, each with different counters. In singles it's 1v1, so you can't easily scout with protect like doubles or overpower the overcentralizing pokemon with two attacks. With Mega Lucario for instance the entire game was played on a gamble. Basically if you guessed which coverage move it had wrong you lost your "counter". Back in the D/P era the game adapted to Garchomp, the top dog at the time.
Do you know what teams in the D/P era looked like?
Ttar/Chomp/chomp counter1/chomp counter2/counter counter 1/counter counter 2. The metagame adapted, and it was so goddamn centralizing that the game basically consisted of 8 pokemon. Sometimes big threats need to be banned rather than adapted to purely for the sake of making the game varied and enjoyable.
> when banning the strongest thing will just make the second strongest thing take its placeThis also isn't true. After the Garchomp and Salamence bans in gen IV for instance the game reached in equilibrium where the OU team was fairly balanced and nothing was particularly broken.