I've been subscribed to this guy for some time. His work is much more impressive, and IIRC, he either works for a defense contractor or is studying for that.

I think there's lots of people talking past each other on this post. These kinds of designs won't be as reliable as the existing designs, and they may have a systemic flaw, for example, susceptibility to disabling with microwaves. And they aren't going to work after sitting in an ammo depot for 15 years in the desert or after being dropped from a plane.

But these designs will cost just a few dollars more than the equivalent dumb munition (and can possibly be retrofitted), and can be two orders of magnitude more effective in the short term. The threat here isn't "guy in garage makes MANPADS", it's "IRGC converts 100's of thousands of existing unguided cold-war rockets into guided S2A and S2S missiles for $20 each". Even if it doesn't hit any target, each aircraft has a limited number of countermeasures and has to return to base if they run out or risk being hit.

Guided munition at a dumb munition price is enough to invalidate many strategies.