Both things are true.
There was a far more vicious shaming culture 50-70 years ago about things like being obese. And culturally it's still looked down upon to be obese, it's just not as acceptable to be vicious about it (and of course sometimes people still are).
Today however there is a lot more "always on" pressure: social media is a huge component to social, social acceptance, socializing, social learning & sharing, getting to date people, et al. That's a form of individually focused media pressure that didn't exist back then. And sure you can turn it off, not partake, but there are usually serious consequences especially for younger people.
That's the context.
Non sense... There were not a particularly big stigma about being obese 50 or 70 years ago. Socially stigma were more about gender roles, sexuality etc...etc...
I didn't say it isn't true that people were shamed more often in the past, I said it has little to no explanatory power of the current health crisis because obviously there is no lack of desire from people to be slimmer.