You're correct... many of the earlier presidents that are still revered and celebrated to this day are people who had views, that by today's standards would be considered ghastly.
Case in point:
Anyone remember this quote?:
"I am not, nor ever have been, in favor of bringing about in any way the social and political equality of the white and black races ... I am not nor ever have been in favor of making voters or jurors of Negroes, nor of qualifying them to hold office, nor to intermarry with white people; and I will say in addition to this that there is a physical difference between the white and black races which I believe will forever forbid the two races from living together on terms of social and political equality. And inasmuch as they cannot so live, while they do remain together there must be a position of superior and inferior, and I as much as any other man am in favor of having the superior position assigned to the white race."
That's Abraham Lincoln... someone who's on our currency, and often gets discussed in terms of being some sort of pioneer for racial equality.
There's an anti-Trump group named "The Lincoln Project" that often condemns Trump for "racist dogwhistles and rhetoric"... meanwhile, their group is named after a guy who didn't even use dog whistles, and openly said "I've never been in favor of making voters or jurors of Negroes or interracial marriage"... let that sink in for a moment.
FDR's Japanese internment camps would rival any level of racism Trump has been perceived to have exhibited, and his attempts at court packing and his 3000+ executive orders would suggest that he had more of a "Kingly ambition" than Trump, yet, the people at the "No Kings" rallies who are appalled by Alligator Alcatraz will undoubtedly have a somewhat positive view of FDR.
Lydon Johnson (who some progressives celebrate for his enactment of the various "Great Society" programs), per
Snopes, wasn't a particularly nice guy... saying things like this:
He referred to the Civil Rights Act of 1957 as the "n-word bill" in more than one private phone conversation with Senate colleagues. And he reportedly said upon appointing African-American judge Thurgood Marshall to the Supreme Court, "Son, when I appoint a n-word to the court, I want everyone to know he's a n-word."