I'm also certain some folks believe Biden was President during the start of COVID-19 in the US too. (Jan 2020.)
It seems to be a pattern, where a disturbingly-large minority of people remember nothing but the year-number of an election (e.g. "2008") and never account for how voting was at the end of that year and the voting-result only takes effect the next (odd-numbered) year.
Oh, there's also a general "I want it to be true so I remember it that way" aspect, but I think that's contributory rather than the main cause.
It seems to be a pattern, where a disturbingly-large minority of people remember nothing but the year-number of an election (e.g. "2008") and never account for how voting was at the end of that year and the voting-result only takes effect the next (odd-numbered) year.
Oh, there's also a general "I want it to be true so I remember it that way" aspect, but I think that's contributory rather than the main cause.