So, we've established there is fishing, game fishing and sport fishing.
There is chess, as a game and there is chess as a sport.
Although I am sure you meant that facetiously, you have touched upon the old Indian saying "Chess is a sea in which a gnat can drink or an elephant can bathe."
If you regard chess as EG does, as a trivial game of chance like ludo, but have no ambition to get any better, then you can still have some fun playing. However, once you get hooked and become a good player, that never leaves you. OK, you forget detailed tactical manoeuvres relating to endgame play when you are out of practice, eg Q & K v R & K, but you never go back to the random moves of the complete beginner.
It is quite a well-known phenomenon in chess that, unlike other sports, once you are over the hill your body doesn't tell you when it's time to give up, even though players are usually in steady decline from the age of about 30 onwards. Rather than find themselves overwhelmed by a tide of up and coming youngsters, top players do retire because they cannot handle seeing their standard decline. Others struggle on.
A pal of mine was stiil Southend Club and League Champion right up to his death. He was British Boys' Champion in 1934. I wonder how good he might have become had he not spent 3 years in a Japanese POW camp. He once told me "I was one of 300 to go in. Only 25 of us came out."
Edit: the Irish sports council once rejected Chess as a sport on the grounds that it isn't sufficiently "technical or tactical". That just demonstrates how ignorant they were. I doubt if there is any other game, physical or mental, which involves as much in the way of tactics and technique as chess does.