“am I just imagining some idealistic version of the past that never existed”

yup.

Americans have always been this stupid, but stupid people aren’t the problem.

everyone is stupid, greedy, or otherwise morally corrupt at some point or another or in some situation or another, that’s why legal rights and protections were so important, to keep the playing field level and the trains running on time when the assholes wanted to run riot.

the successful conservative suppression of civil rights and removal of restrictions on corporate and wealthy political stuff civil activity, particularly the allowance by the Supreme Court of money to dictate political action, has removed the guardrails that used to protect the stupid and keep corrupt people in line.