How many hours do you think the ukie pilots got before the war monthly? Now stick them in a new jet that's 'easy to fly', still won't be getting hours, not flying to Warsaw, they have to fight the plane, not just sit in it. Simulators are no replacement for flighttime despite the claims of the manufacturers. If they got the planes they would have to train in ukeville which means those bases become targets, any who actually flew in combat would be butchered by the Russkies by air to air combat or the S-400 SAM.
If they get the planes they can train in a lot of countries, which have offered training facilities.
The main uses of F-16s in Ukraine as I see it
1. As a CAP, covering several regions, looking to shoot down cruise missiles, to be a more flexible extension of the SAM system. The F16 should be good at this with its radar and AMRAAMs. The Ukrainians are running low on S300’s and probably want to reserve them for manned aircraft. There is no shortage of AMRAAMs.
2. Pop up launch of SDB or JDAM. This is something that the Ukrainians are already doing some of, but the F16s should be better at it. https://en.wikipedia.org/wiki/Toss_bombing
3. Should the Russians get inspired to risk losses and commit a large strike package into Ukrainian airspace, the F16’s can likewise be surged to oppose it, much better than the Mig 29s. They have much better radars and missiles. This is insurance, just in case the Russians change their behavior.
I doubt very much that Ukraine intends to commit the F16s into the Russian Air defense zone.
I don’t have an answer to your question.
How many hours do active Russian pilots get for training, how much of it is combat training? How familiar are Russian pilots with their air frames? How updated are the recalled pilots in Russia? How many hours a month do ‘reservists’ fly in Russia?
The Ukrainians will be fighting against Russian pilots, over Ukrainian territory. I suspect that some of the Russian pilots are amazing, some probably many not so much or ‘recalled’ with little recent flight time.
I think the SAM’s are probably a bigger problem. They have proven to be quite lethal for aircraft over Ukraine.