Because that’s exactly what they’ll conclude if Republicans “move on”, and nobody dares to fight back or even talk about it.
Trump and his supporters talk about it daily and fight every day, and the other side talks 'big lie' and dismiss every claim Trump and team make. Why? Because in spite of all the evidence claimed none of it has been taken to court. Unless and until someone is charged, tried, convicted, and sentences for vote fraud relating to the 2020 election then all it is is talk.
Yes, rapists like it when their victims shut up.
The Courts are garbage, and there will be no relief to be had from that direction.