as per me
chess is a sport
is because it has enough or more than enough things to be considered as a sport
like preparation, diet, money, etc
and about the "It does not require physical exertion"
think twice about it tbh because it tougher than it (playing 6hr nonstop chess is tough)
and about other sports
it requires both physical and mental power
it is true that other sport is more physical than mental but it requires both
but people see it as pure physical power which as per me is completely wrong
to sum up
for eg purpose
chess = 70% mental power & 30% physical power
other sport =70% physical power & 30% mental power
nope. if chess is a sport so is doing a crossword puzzle.
https://www.youtube.com/channel/UCosWMmRMW3HkoRMs-KaKZFw