Who said he cheated? He lost the popular vote, in fact.
The claim of cheating was his, that that's what was done in favor of Hillary, and that was the reason for his loss in 2020. Why that simply wasn't done in 2016, however...
The assertion is that Putin's RT and IRA utilized propaganda via social media and whatnot to help Trump's campaign image and to whip up fervor. He didn't go from joke to cult simply because his base had an epiphany about what a swell guy he was midsummer.