The so-called "evidence" has either been thoroughly debunked, proven to be an irregularity that was taken into account, or simply never existed. And any instances of individual fraud, if any, are still extremely rare.
And if any of the courts have so far failed to look at any of this so-called "evidence", it's because it was never presented in court by the plaintiffs.
Trump is chasing windmills trying to find something, anything, that will let him stay president another four years.