The goal of government should be to ensure that power serves the people.

Who told you this? The people in power, perhaps? Surely they would never lie to you... would they?

The idea behind democratoc forms of government

There is no such thing as a "democratic" state - the society you exist in is either democratic or it isn't. Spoiler alert - yours isn't... which means it doesn't matter how loudly politicians or the media tell you how "democratic" everything (supposedly) is, does it now?

If US society was in any way democratic, you'd have something resembling universal healthcare already - which you don't.

If US society was in any way democratic, the US wouldn't be the world's number one warmonger and funder of fascist terrorism - which you are (and have been for a very, very long time).

it will seek to serve the people.

So do tell... how has helping a genocidal white supremacist state perpetrate mass-murder on brown people half-way around the world "served" you today?

The thought-terminating cliches - oops, sorry, I meant to say "theories" - you have been sold isn't matching up with blatantly observable reality, are they?

Perhaps you need better theories? Or, at the very least, theories that actually qualify as theory?

Power will always serve it’s own self-interest

Yes... it will. And institutionalizing power is simply the most logical way for power to serve it's own interests.

I am having difficulty imagining such a system.

That's because you're not supposed to - in the same way that peasants were not supposed to imagine existing without "divinely ordained" families of inbred charlatans lording over them.

If you live in the US in 2024, you have the option to vote for Donald Trump, Joe Biden, or abstain.

This is a very liberal thing - even these (so-called) "conservatives" (who are really just liberals far along the "liberal-to-fascist pipeline") are willing to contemplate shaping politics outside the formal political establishment. But liberals naively believe any such thing is impossible - someone should really study this.

How is abstaining or voting for Trump helping anyone?

There's a lot more to politics than just elections, for crying out loud. Did antifa wait for an election before beating the fascists off the streets in 2016?

so maybe by ensuring a Trump presidency you can accelerate the destruction of the current US government.

Lol! The only thing a Trump presidency is going to accelerate is the Dems being able to run a blow-up doll in 2028 and knowing perfectly well that people will turn out in force to carry it into the Waffle House after four years of Trump's abuse. The US political establishment is far too large and labyrinthine to be brought low by one person - it's going to take a lot more than Trump. You know... the guy whose brilliant idea of a "coup" was simply to sicc a white supremacist lynch mob on the capitol?