Even if there's no consensus on whether some beliefs are good or bad, such as in politics, doesn't hypocrisy show some sort of "character flaw" in the perpetrator? It's dishonest to push views you don't hold yourself, or rules you don't even try to live by.
Regarding showing dishonesty - yes, but "supporters of X are dishonest" is "ad personam" - that's poor argument.
Better to use hypocrisy to show "even supporters of X don't really believe their view is right, so it probably isn't".
Still, not a good argument.
Their view could be right, whether they do really believe it or not.
E.g a politician could say "don't steal", and he could be stealing himself. That he is hypocritical about it, doesn't mean stealing is "probably" right.