Yeah that's actually something naruto-fans have been arguing over for a long time. It's why fanfiction often has Naruto's henge be special and 'real' (which is honestly even stupider). Other fanfiction use this to the point where naruto essentially goes around using it to the fullest extent. The only reason this doesn't really get out of hand like other broken powers in other shonen, is because the more complex the henge, the harder it is to keep up for longer times, which limits its use to those people with chakra to burn (like Naruto). https://naruto.fandom.com/wiki/Transformation_Technique
Interestingly, since it's not a hard technique, it can be down one-handed, meaning a person missing a limb can temporarily return their limb for some time.