Russia has vastly more warplanes than Ukraine does, and its warplanes have suffered only comparatively light casualties in the Russo-Ukrainian war. And, NATO forces have not been willing to put their own military forces into action in Ukraine even though they have been generous in supplying Ukraine its military equipment to resist Russia's attack on it, and have imposed economic sanctions on Russia as a result of its military actions. Despite this clear military advantage:
Russia has been reluctant to deploy its airforce over Ukraine since it launched its full-scale invasion of the country[.]
(Newsweek). See also here, reaching the same conclusion.
The underuse of the Russian Air Force in the early days of the Russo-Ukrainian War baffled military experts. (Al-Jazeera cited other military experts who were likewise baffled.)
Several theories have been advanced to explain its reluctance to use its air force in Ukraine:
British intelligence has argued that this is "due to the danger of a strike against Russian airfields and the "continued high threat" of Ukrainian air defenses[.]" See also here, reaching the same conclusion.
Another possibility is that the Russian Air Force is a paper tiger whose publicly stated aircraft resources are exaggerated and that it isn't actually able to deploy most of its planes in combat because it has a low state of readiness and because it may not have the right kind of aircraft for this conflict or make lack sufficient aircraft delivered bombs and missiles that are functioning.
A third possibility is that Russia feared that doing so would make it more likely for NATO Air Forces to intervene directly, perhaps establishing a "no fly zone".
A fourth possibility is that Putin has less loyalty in his Air Force than in other parts of his military and that senior Air Force generals pushed back on the Ukraine War in general and their units playing a major part in it.
Why has Russia made surprisingly little use of its Air Force in the Ukraine conflict? And, are its reasons actually well-founded ones, or are they simply caused by the dysfunctional organizational culture in the Russian military?