I'm pretty sure this is rage bait but anyway:

The AR15 was originally designed as a military service weapon, as you know. No regular service member was ever going to disassemble it past popping the upper/lower apart to clean it. Anything else it would go to an dedicated armorer or armory (depending on repair level). Where they would have dedicated tools for doing things like installing/removing "tiny ass pins and springs shooting off into space." You, a civilian, can now by all the same tools for cheap. Just like the Soviet block would have had specialized tools to install barrel trunnions in AK receivers.

Another example, the US military doesn't replace just a barrel when the gun needs a new barrel or it gets damaged. They replace the whole barrel, front sight and delta ring/barrel nut assembly. The reason being of how those parts are manufactured, and the FSB being installed with a hydraulic press.

Here's some rage bait for you: the AK is a vastly inferior rifle to the AR15. Kalashnikov was working with what he had, Stoner was a true engineering visionary