It isn’t about people better than you. It is about idealized and generally unrealistic body standards.
The new guidelines, now introduced in the UK and around the world, apply to content that: idealises some physical features over others, such as beauty routines to make your nose look slimmer; idealises fitness or body weights, such as exercise routines that encourage pursuing a certain look; or encourages social aggression, such as physical intimidation.
These are not videos about getting to a healthy weight and exercise routine. “Certain look” is a crappilly phrased way of saying unrealistic body standards, but that is what it means.