Democrats (see masking, see vaccines) are more weary of the virus. Hence, substantially more Democrats took advantage of in-person early voting and mail in voting. [Highly doubtful that in-person voting broke 71% for Trump. The PEW research link I posted does not support your numbers].
Polls show Republicans are substantially less trustworthy their votes will be counted, explaining why they prefer in-person same day voting.
Your argument false as you have never established any evidence that mail-in voting is less accurate. All the groundless legal challenges were swatted away by the courts.
Read Raffensperger's new book.