F-16s are great, don't get me wrong, but what they need are Grippens from Sweden.
We design the F-16 with our own needs, capabilities and doctrines in mind. It's a warplane designed for us. While it comes with all the bells and whistles you could want, it's also extremely demanding to field and maintain. You need a large, secure airbase to use them from. This means Russia is always going to have an idea where the F-16s are, because there's only so many places they can possibly be.
The Grippen was designed as more of a guerilla warplane. You can hide it in a forest, keep it maintained with a handful of guys and a truck, and launch it from a random highway. You never know where a Grippen might be.
This heightened flexibility is exactly what Ukraine needs right now in a warplane. And we (Americans) just never bothered to design one like that for ourselves, because it wouldn't do us any good. What would we use them for, asides giving them to Ukraine? Sweden already has one, designed, produced and tested.