F-35 took nearly 3 decades.
As it stands US tech companies don't want to do high volume low cost drones, so ukraine will likely end up doing it and become the supplier for other countries.
I mean looking at the state of that conflict… the low-cost drone thing doesn’t look that great. Maybe other countries will want to go with this kind of attritable aircraft concept instead.
https://en.wikipedia.org/wiki/Low-cost_Uncrewed_Combat_Attac... is almost a straight copy of the infamous Iranian Shahed for ~$35,000 USD. (Perhaps the US sourced their Shahed from Ukraine, though that, like many things about this program, has not been officially discussed.)