In order for Donald J Trump to win by a landslide he is going to have to win the popular vote by 20% more than Joe Biden and he is going to have to win over 70% of the electoral vote.
That is not very likely to happen.
If anything, Donald J Trump is going to lose the popular vote and win the Electoral College Vote by less than 60%, and that’s only going to be because Amy Barrett is going to hand him the election regardless of the will of the voters.