Especially because the US doesn't even employ direct presidential elections, but uses the electoral college. A third party candidate simply will not win. Any obfuscation of a clear win will make it that much easier for the electors to disregard the people.
I'd like to remind you that Trump is still actively pretending the last time he didn't lose, and even when he was elected president, it was against the popular vote.
So yes, by not voting for Biden, you are helping Trump, like it or not. Which you clearly do, with the whole "this is why people don't like democrats". I'm not American, and you still result to trying to mock democrats, clearly implying you're a republican.
And thus you probably actually know you are helping Trump and you're fine with it, you're just ashamed of letting people know that's what you actually think.