that is outdated advice. for one, some people sweat more than others, the salt levels in the sweat is totally different too. this means that if you're really serious about sport or are doing endurance races (ie 2 hours+) you should really not just use gatorade, but something where the mix of salt/water is closer to whatever you're sweating.

if i personally use gatorade for endurance exercise, i'll just cramp up after 90 minutes and not be able to ride normally. if i use a high salt mix instead, this isn't an issue whatsoever. I'm sure the exact same is true about food itself. remember that for the tour de france, last years time difference between the winner (Vingegaard) and the second (Pogadcar) was 8 minutes out of 82h 05' 42", aka only 0.16% faster overall. every single sub-percentage matters here.

there are tons of products that cater to this. the one i've been using is https://www.precisionhydration.com/ which is cheaper and more tailored than gatorade (i have no affiliation to them).