In that theater, yes. Or equal enough that Russians dont have a big advantage. It's always easier to defend than attack, even in the air.
And to your racis in question, I think it's clear that the Russians werent expecting this much resistance. See the liberation argument made by our Russian "non" apologists. So they may not be set to defend against attacks because they didnt foresee it happening.
Also from a logistics standpoint those helicopters could have come from any clear field in Ukraine. While jets/anything without VTOL need a runway. So it's easier for the russians to watch for attacks from runways and other known areas, while the helicopters may have taken off from Farmer Ivan's field.
And like others have said Russias military may not be all its cracked up to be. I am still in the camp that Ukraine is just fighting the conscripts, not the real Russian army. While a lot smaller the real Russian army would probably have done a much better job. But I dont think Putin wants to risk them in guerilla warfare while NATO still looms.