Though they were once the dominant genre in the '50s and '60s, certain Western movies ended up being popular because they were so controversial. Controversy in Westerns arose from all sorts of issues around violence, race, and societal norms of the era, sometimes inspired by something on set during filming, but often the overall quality of the released project. In almost all cases, the same things that were deemed controversial 70 years ago would be considered the same today, except for a select few that can benefit from society's more modern and tolerant set of standards.

https://screenrant.com/western-movies-most-controversial/