Wrong, as Justice Thomas makes clear in the first paragraph of his dissent:

"The Constitution gives to each state legislature authority to determine the “Manner” of federal elections. Art. I, §4, cl. 1; Art. II, §1, cl. 2. Yet both before and after the 2020 election, nonlegislative officials in various States took it upon themselves to set the rules instead. As a result, we received an unusually high number of petitions and emergency applications contesting those changes. The petitions here present a clear example. The Pennsylvania Legislature established an unambiguous deadline for receiving mail-in ballots: 8 p.m. on election day. Dissatisfied, the Pennsylvania Supreme Court extended the deadline by three days The court also ordered officials to count ballots received by the new deadline even if there was no evidence—such as a postmark—that the ballots were mailed by election day. That decision to rewrite the rules seems to have affected too few ballots to change the outcome of any federal election. But that may not be the case in the future. THESE CASES PROVIDE US WITH AN IDEAL OPPORTUNITY TO ADDRESS JUST WHAT AUTHORITY NONLEGISLATIVE OFFICIALS HAVE TO SET ELECTION RULES, AND TO DO SO WELL BEFORE THE NEXT ELECTION CYCLE [emphasis might]. The refusal to do so is inexplicable."

These were Constitutional questions which should've rightly been debated and decided by the Supreme Court.

Confidence in who is allowed to set rules for an election is critical for citizens to believe that elections are fair and legal. Refusal to establish precedent in this case presents the possibility of ambiguity being injected into future elections where state legislative and judicial authorities election rules conflict.

This had nothing to do with the despicable January 6 incursion on the capital nor was it an attempt "to validate the notion that Biden's victory was stolen".