Sure they can. The Supreme Court rejects 97% of the cert petitions submitted to it. Most of those cases don't have procedural "errors"; the court just decides it doesn't need to hear them.

It would be very easy to decline to hear these. The suits primarily focus on alleged technical violations of state election laws. All SCOTUS has to say is: "Questions about state law are for state courts; those courts have ruled and we see no reason to second guess their judgment."

If they wanted to hear these cases, they could have granted the Trump campaign's motion for expedited review before January. The fact that they rejected that motion suggests that they're not that interested in hearing them period. They may decide to go ahead and hear them given the enormous public attention, but I wouldn't be at all surprised if they decided to pass. At this point the general public has probably forgotten about the suits or assumes they're already dead, and the MSM will run a 200 word "cert denied" story on page 27.