Has the lack of crypto ever stopped this from happening? Look up cases of gold bars being found in senators houses, those are actually MUCH less tracable.
Shitcoins and Shitstocks(some SPACs) do allow of a legal way to "give" others money through the transfer of value in a way that is technically legal. This again is not crypto specific though.
So the best part about being bribed with crypto is if one flees to another country to escape the law, one still has the aforementioned bribes. That plus some measure of anonymity.
Anonymity is the one thing cryptocurrency does not do well. It's much harder to sieze but much easier to trace.