i agree with the half your age + seven rule....to a point
for example, in my real actual life, a 21 year old college guy who is closer in age to me has started pursuing my 16 year old sister which i find WILDLY inappropriate and i have to keep reminding her to think about "why isn't he dating girls his own age and has to pursue highschoolers?"
i agree with the above, when it comes to minors, age is super important and the dating difference should be 2/3 years max, meanwhile, once you hit your 20s you can start to stretch that range all the way up to dating people in their late 20s etc