It’s enough to learn when you are being gaslighted about machine gun ammo consumption. Yes, it eats ammo faster, but it is also more dangerous. Furthermore, being fully automatic doesn’t mean you spam it until it consumes the whole cartridge, it means you have more control how many bullets you can track with each trigger engagement. It’s why burst mode exists, but better. People do have an idea in how to control ammo consumption, it is a core game mechanic with most games with guns.