While I agree with you that the past should not be romanticized, much of what you're talking about was in the 50s and early 60s, not the 70s and 80s.
Attempted suicide ceased to be a crime in 1961; homosexuality in 1967 (though same-sex marriage was not possible till about 10 years ago). So far as I know, mixed race marriage was never illegal in the UK, though it was socially disapproved. It was illegal in many American states until the 1960s, but not here.
I do think that the idea that people looked and felt healthier in the past is incorrect. Obesity is commoner now, but is not the ONLY unhealthy characteristic that a person can have. People in the past were, for example, much more likely to smoke, and much more likely to work in dangerous and unhealthy conditions. People usually had a much shorter life expectancy.
I think that much of the idea that people in the past were healthier comes from the fact that there were far fewer elderly people when life expectancy was shorter! Also, people with health problems and disabilities were less visible. Severe problems were either rapidly fatal, or resulted in institutionalization. Milder problems were often not even slightly accommodated before the Disablility Discrimination Act, and often resulted in people leading very restricted lives, physically, socially and financially, and spending much of their time at home and outside the wider society.
Also, people may think that 'health was better in 1982 than 2022', when they really mean that their own health was better in 1982 than in 2022. Which is probably because they were then in their 20s and are now in their 60s.