depends what you mean by 'good'.
fighting games are weird in that before you can even 'compete', you need to have the prerequisite of knowing how to mechanically input special moves and combos, including memorizing combos.
some people are 'bad' in that they just have difficulty in inputting combos or special movies at an accurate level.
at a very basic level, you can be 'good' at a fighting game when you: 1; can consistently input specials and combos, 2; memorize several combos for common conditions, 3; learn the matching of your character vs others.
to be 'very good' is just to do all the above, but also have an understanding and feel of your opponents plans, and to correctly and quickly react to disrupt your opponent and set up your combos -- although how quick you have to be depends on how well you understand your opponent, and the matchup
to be extremely good is to be able to do all the above, just at extreme consistency. you never drop combos, you never miss an opportunity to punish, you react correctly and quickly and constantly disrupt your opponent, and on top of that you can improvise unorthodox moves and adapt on the fly, not to mention perform all this in high-stress situations
so i would say most people with time an dedication can be good to very good with practice, lets say top 15-20%. although to be very good it might rely on understanding how to compensate for your individual weaknesses with character and move choices. to be extremely good, like top 5% probably relies both on a lot of practice but also a lot of talent.
(t. someone who doesnt care for and is bad at fighting games)
>>717607172
probably any fighting game where they have essentially instant death 100 move combos, because you fuck up once and you die like marvel vs capcom 2 or something
