https://ballotpedia.org/Analysis_of_uncontested_elections,_2024
Please consult my comments section for the mainstream explanation for why the US is totally a democracy and ever was. All I have for you in the meantime is communism. Liberal democracies are fake as a rule.
I know where I live, there used to be better elections, historically. The gerrymandering, emigration, etc just led to everyone else giving up.