This was exactly the explaination from the old Exoanded Universe/Legends in Star Wars. The most sophisticated piece of any fighter was their EWAR suite. Otherwise fighters would be wiped out from well beyond visual ramge by capital ships’ point defense systems, and it’s why they needed to get so close so their sensors could power through the jamming to get missile locks on other fighters.

Also my head cannon for Battletech, and is explicitly the reason why Gundam fight so close.