Many of the cases were dismissed on the merits rather than just on standing. In the cases where judges looked at an argument from someone who did have standing (there were several of these in PA), they consistently found that there was no merit to the arguments. This was largely because Trump's lawyers were making entirely different arguments in court than they were in the press. Well, arguments in the press don't count. Several of these cases were appealed, including a couple that got the appeals to request a Supreme Court hearing. Denying a hearing on the appeal means that the Supreme Court saw nothing wrong with what the lower courts concluded. The cases were heard and found lacking. A case that is lacking in lower court doesn't get heard at the Supreme Court just because it would appease a political party.

Some were dismissed based on laches, where the judges concluded that you can't challenge a rule that you let slide before the election. Again, they had their day in court and were found lacking.

In short, it wasn't just cases getting kicked for standing. Plenty of people CAN contest an election. Plenty of people DID, including Trump and his campaign. Their cases were heard and found to be completely meritless. They've just been peddling lies in the media because people in this country don't read the news with a good understanding of civics.