Lawfag here. If the courts don't have jurisdiction, they would say so. It was obvious these courts were all looking for a way to avoid being the judge who potentially disenfranchised an entire group - or all - of the ballots when the plaintiffs weren't precise about how many ballots were affected and whether they could prove that these ballots would change the outcome of the election. Those judges would have jumped at saying they had no jurisdiction if that was the case.

The courts certainly have jurisdiction when someone sues alleging state/federal law wasn't followed. Or when the Constitution was ignored. They even have jurisdiction when there is no obvious harm to the plaintiff.

In this group of cases, each judge fell all over themselves to get rid of the cases, often ignoring the claims in the complaints altogether. They came up with lack of standing, they came up with failure to state a claim for which relief can be granted (no available remedy), they came up with failure to name necessary parties, they came up with standing (the plaintiff has suffered no personal harm or there is no connection to the actions in the pleading and the damage to this plaintiff). Many courts added gratuitous language saying the time to sue would have been before the election rather than after the fact ... which is nuts because those same courts would have said - if the cases were filed before the election - that there has been no harm suffered.

Bottom line, it was clear that judge after judge used every possible way to get rid of these cases. Were they afraid of being the judge that single-handedly gave Trump the victory? Were they influenced? Were they Democrats? Who knows for sure, but when you see 50-odd judges falling over themselves with different reasons to dismiss cases all over the country, with different rationales on basically the same set of facts and legal theories set forth in the various complaints, then either you have to conclude that Trump's legal team was absolutely inept (not the case) or the fix was in.