Even if Trump? Trump is by far the most popular republican in the country and got more votes than any sitting president. He would be her biggest threat to winning compared to basically any other candidate.
Trump has the highest floor and the lowest ceiling. People love him and people hate him.
You correctly claim that Trump got more votes for any sitting president, but it’s disingenuous to omit that he also got the highest vote to reject a sitting president - even if you assume that 20 million of Biden’s 81 million recorded votes were fraudulent!