I believe most of the accusations about 2020 were centered in places where the Democrats were in power like Philadelphia and its suburbs.

Control of the WH is immaterial because all voting is controlled by the states or local municipalities.

Another part is that the Republicans were much more prepared this time to stop the alleged fraud before it happened. They had lawyers ready to protest immediately when election judges were locked out of counting rooms or when counting stopped. They made sure they had enough election judges for all precincts and sometimes they set up cameras to count the number of voters entering the site.

Perhaps your point about polling is still the best answer