This is a flat, substabtial interface with the 10th Amendment’s allowance of states to manage and run elections. If a state allows elections such that they aren’t denied on account of race, gender, and people under 18, they can be run however the states deem. Requiring someone to register with the federal government is not a power of Congress
I think not only that, they want to make sure they have all the kinks worked out in their system before the next presidential election. He’s going to run, there’ll be legal challenges but he’ll do it anyway, he’ll win and use that to justify that it’s the “will of the people”, SCOTUS will rubber stamp that excuse, Congress will cheer like they did when Palpatine declared himself Emperor.
Maybe after they rig this one more people will start recognizing this is beyond a problem that can be solved with elections.