There are actually all sorts of legal reasons why all Trump's coup nonsense is not going to happen. First of all, 49 states and DC certified their elections by December 8, the "safe harbor deadline". Congress is obligated by federal law to accept those elector slates. States can't "decertify" and substitute slates. Then the electors got together physically or online in each state on December 14th to record their votes. Then by December 23rd, all state certificates were received by the appropriate officials in DC.

The next step is January 6th, when Congress meets to count the electoral votes according to the state certificates. If a member of each house objects, they debate for a while, and then both houses vote on rejecting those state's certificates. If they both have simple majorities in favor of rejecting a state's certificate, then the coup could continue. But they won't. The votes are by individual members, and Democrats hold the House. But I'm pretty sure the Senate will vote to accept them as well. So all the state certificates will be accepted.

Then on January 20th, Biden becomes President, and Trump is arrested. On January 21st, all the congressional coup supporters are arrested and charged with treason. Nope, just kidding! That's what Trump would do. but not Democrats.