Will this experiment in the USA we call democracy last?
No
Certain politicians have to take an oath of office. Who enforces that oath? Political appointees that's who. Who gets prosecuted for not upholding that oath? No one. Even if Trump is prosecuted it certainly won't be for not upholding his oath of office.
What about term limits? How can they be created and upheld? By politicians and they aren't going to do that. Hasn't happened yet and isn't going to happen.
Simply put democracy continues in the very watered down way it does based upon people's ideals of democracy. You get some people in power that don't give a shit, democracy dies. It almost died a few years ago. It's likely going to die within the next 50 years and likely much sooner.
Please someone rationally explain to me how and why I'm wrong.
We are already the longest running democracy so, if the idea isn't sustainable, we are due for the fall. Yes, this might be it. I don't subscribe to term limits but I do think there should be a mandatory retirement age (for SCOTUS as well as Congress).
Putin and the fascist Christians have mounted a highly organized attack, much of it based on psychological warfare. Having already made inroads into the military and intelligence community, the latter either chose not to defend or had no defenses. Installing Trump set up the country to lose the SQOTUS. Given the wholesale firehose of corruption spewed by the GQP, no one is up to the task of getting the reins of power back. The Pentagon and FBI have failed in the worst ways possible. How things fall apart may well get very ugly. The GQP wanted less government, but their treachery will turn on them soon enough.
Shame on the voters who didn't vote in 2016. Shame on the Military Industrial Complex for leaving the country open to attack. Shame on the GQP, although they are subhumans incapable of knowing of shame or feeling it. Same on the dems for their corruption, hubris and stupidity.
You're not wrong, though your first guess at a timeline is really optimistic. I would be willing to bet it happens in the next few election cycles. Two independent organizations who measure the health of democracies around the world have already downgraded the US from a "full democracy" so you could kind of already say it's over. I mean, there's rarely an exact day where you can say, "That democracy fell then!" It's gradual, and that's why it's so successful. If Trump were less polarizing and a lot smarter, it would have already happened.