(1)If you have any of the conditions of people here for getting and keeping in shape team sports like ball games are a problem or non starter.It's also why many of us can through experience not be team players generally in life.
(2)If you have problems learning to drive then private transport can be out to getting to a local authority gym and leisure centres and a pain having to use public transport.
(3)Given that such people can have these problems in the field of exercise how are such people supposed to be incentivised to keep in shape?
It is assumed you can easily be employed, (if its not a going nowhere thing) can easily drive to such places in a vehicle and that all of this can be easily afforded, and you can do things (other than the gym or a pool) that aren't just going to make you feel like a reject which is why many such people here were probably really ANTI-PE at school.
It's also the sort of thing that stops men in particular from doing jobs in the services because problems with hand eye cordination et all are not expected.(Cant play football your a w****r mentality.)
So is it at all understandable that if people here start getting comments about their waistline or being told they are in danger zones for obesity that might warrant a F""" off reply because in many of our lives what we eat and drink is one area where we have some ABSOLUTE power over!
Speaking for myself If I am expected, as a big guy, to look more like Dolph Lundgren or Arnold Schwarzennegger than James Corden then I take the view that these other obstacles relating to neurology that have wider implications than just how in or out of shape I am have to be dealt with first!
I otherwise feel like a cigar smoker being told by a Doctor to give up who just wants to puff it right in their face!
Extend your physical life for as long as possible when the terms in which it is being lived are generally unsatisfactory. WHY?

P.S. The only other reason I can see for being "fighting fight" is for self defence and to wallop anyone hard who has offended me in life over my neurological issues.An idiot educational psychlogist once suggested martial arts.I tried karate and it just made me feel like a reject.