I expected Russia to steamroll Ukraine in a few days, but it didn't happen for a few reasons that I doubt will change anytime soon.
1) Ukrainians are willing to fight and die for their land. (And the west is willing to supply them)
2) Russia is nowhere near as effective in combat as they appeared they would be prior to them starting this war.
3) Russia's effectiveness seems to have been hollowed out by corruption.
Yeh. Any notion that they could take on all of NATO in a conventional war is quite clearly utter folly.