This just isn’t true, it is easy to find blatant corruption tied to politicians at all levels from both parties. Look at California, New York, Chicago, and Baltimore, look at the Biden family, the Clintons, Nancy Pelosi, Letitia James, the Democrats are just as corrupt, the mainstream media just reports on it less.
I think it's naive not to see the "both sides" card get pulled anytime there is a criticism of the right. All the "centrists" come out to hold water for conservatives when their policies are clearly and specifically failing.