I don't think anyone expects PLA to be used for anything that requires structural stability. There's far better filaments for that application. Some of the carbon fiber infused PETG filaments for example are incredibly strong.
Not many people use 3d printing for applications that require extreme strength though, that's really not the goal many people are aiming for.
You would be surprised!
I do this for a living and people are always looking for more parts to run through the process and better filaments to see those parts end up performant.
CF-PETG is strong! For a bit more toughness and temp resistance, PA12CF35 is seeing a lot of use. Some companies out there have service departments to keep machinery running. They apply FDM more than you might expect. Alloy 910 for gears, Cf of various kinds for abrasive scenarios, like cardboard handling, in one scenario.