Some people out there seem to be confused, but I always vote in every local and every national election for every office and every ballot initiative since I was 18 years old. Some of my greatest civil rights heroes have fought and died so that we can all vote and I honor their memory in the ballot box every single time.
To some of us, especially those of us like myself who have been scheduling secretaries for US senators, it often seems like a morally reprehensible choice between compromised corporate Democrats and fascist-minded Republicans. Where I live in California, I have the luxury of voting my conscience for president for third-party candidates that better align with my ideas of justice and equality.
But in any and every contested race, as my mom Mary Morello always said, we have to fight the fascist every which way we can, recognizing that even if there's but an inch of difference between two candidates, there are a lot of vulnerable people who could be greatly harmed in that inch. So vote your ass off, but don't just exercise your right to vote. Exercise your right to fight for, organize for, struggle for, and manifest the kind of world you'd like to really see without compromise and without apologies before, during, and after election day. And let's stop the fascists every which way we can. Power the people.
Keep in mind that my frustration stems from this sentiment:
No, voting in primaries isn’t going to fix the problem.
So a scenario that is "first, vote for a president who will..." brings us back to voting, so I'm glad for that, just that many folks are saying don't even bother trying to vote.
But putting that aside, and going with the assertion that a President can unilaterally disband the current system and let everyone collectively 're-roll' a new system, this doesn't really pan out either. The assumption stems from a belief that the current administration demonstrates that an administration can act unilaterally. This isn't actually true, he has the support of congress, even if congress likes to sometimes pretend they don't support him. If you had your hypothetical, he'd be removed by congress immediately and the speaker of the house would replace him. Of course that's ignoring the reality that there's no way you vote someone with that position in without also voting in a lot of congress, but again, this scenario involves a lot of popular support expressed through voting. Not amendment level popular support, but enough popular support as to make the amendments frankly not really needed.
But stepping back a bit further, one could put aside the concept of a president and stick more with the historically demonstrated reality that a system can be taken down with less than it would take to rework the system as it stands. The amount of support to amend the current system would be inconceivable the way it works, but systems can be changed in other ways. Those ways amount to a combination of numbers, conviction, force, and cohesion. I just don't see that, and at least some of the folks on that anti-electoral bent have acknowledged that, and have suggested a hope for a collapse event that will draw numbers and conviction. They assume a cohesion will occur that naturally would align with them, despite not putting in the work because it 'just seems obvious' that they are right.
The reality is that people can look around globally and see that the system fails them more than they would like, but grading on a curve the current system resembles the ones that work more closely than it does in much worse systems. Rerolling the system would be pitting people against each other based on conviction to do physical violence, the resulting fear, and numbers. Very high odds you kick that off and ultimately end with an authoritarian state focused on purity of ethnicity, religion, gender and such because those dudes are way more willing to do harm than others.