I don’t find it attractive, but I am willing to hold myself to the same standard. I consider it first and foremost unattractive in myself. As someone who was skinny/lanky most of my life and whose BMI went up by about 7-8 points to the cusp of obesity in an absolute disasterclass of a year in 2021, I can give you an example of how I’m willing to commit myself to the same standards I’d want in a partner. I have been lifting weights every day (which is one thing I was doing before anyway), have completely revamped my diet, and have steadily lost 21 lbs since March and am closing in on reaching back to normal BMI range shortly. I do all this firstly because I find it fun and therapeutic, but also because I want to be what I want to attract, and I also absolutely value health.
Everyone has different preferences (both men and women) and I don’t hold that against them personally, and everyone’s definition of X is different.
My personal definition is tough to define specifically but is a mixture of: