IS, not "was"
And judging the way and length the Russian took Mariupol (still has not fall on day 30), I really doubt Russia can do anything with the entire Donbas region. It's a lot better entrenched than the city, lay out with defensive network, plus you are giving the Ukrainian 30 days to improve the defence infrastructure, also, unlike Mariupol, Donbas region is still opened. Which mean supply is going to flow thru.
I mean if Russia cannot take Mariupol in the next couple of days, they virtually have no chance to take the entire Donbas in the whole 2022, or beyond. On the other hand, Ukrainian is starting to move over to Kherson, once they have retake Kherson (some report suggested part of Kherson is already in Ukrainian hand) that's more or less game over on Russian Southern attack, unless they fancy losing Crimea and have the entire south cut off....
lol, probably not after they just see Russia blackmail the European in this war.
I mean, literally, Russia just burn their bridge on the European, and then turn around and say to the Chinese "Would you want a bite of that apple..." It may cost you some of your land.............lol