That's true to a point. Extra fat based weight is harmful that's just a medical fact.

How much is too much for a specific individual can be somewhat variable, and body composition matters.

BMI as a tool can be clunky and not ideal at times, but if you're more than 1 point off the healthy range and you're not a body builder your health will be impacted (over time).

I'm overweight myself, but I don't try to convince myself I'm in peak condition.

BMI isn't perfect but it's still a good tool to compare two large, similar populations.

And no, being morbidly obese is not healthy.

For country-level data, there is nothing wrong with BMI. There is at best a low single digit percentage of the population who is athletic enough that they're BMI-overweight without actually being fat.

What's crazy to me is that sumo wrestlers aren't actually fat, they eat and exercise in a certain way that the fat only builds up on the outside, not in their heart or anything that would cause health problems. So it's more accurate to say they have fat but are incredibly healthy.