This is the modern GOP.
They support it because the elected (including those who voted to certify the election - Graham, Blunt, Toomey, both Scotts, etc.) officials have supported all of Trump's lies and statements the past four years.
Also, a bunch of people disgusted with the party dropped their affiliation, so you've had a distillation of the Republican Party while the Democratic Party became the big tent party that can include Joe Manchin and AOC.