Which might be a good idea if one were to develop a methionine dependent tumor. Everyone else doesn't really need to worry about it since methionine doesn't cause the tumors so eliminating or even reducing methionine is pointless in any case but one in which the individual has a methionine dependent tumor and then it's a bit like closing the barn door after the horse is long gone.

It's a little like reasoning that goes like this:
Automobiles are involved in 100% of auto accidents. Therefore, automobiles cause auto accidents.
While it's true that automobiles are involved in auto accidents 100% of the time, they are not the cause of automobile accidents.