This was very interesting and (IMO) balanced opnion piece on Russia's chances.

I don't know enough about Russia's domestic polcies to have an opinion on whether Putin can/should/would declare war.

One quibble is that I'd say Russia has had very discriminate artillery fire. As horrible as this war (like every war) is, Russia has killed far fewer civilians than - for example - the US did invading Iraq.

The East of Ukraine was built up with layered, hardedened defenses for the 8 years prior to Russia's invasion. Ukraine knew this war was coming. Poroschenko stated clearly that signing the Minsk agreement but not implementing it was a way to "buy time before the war." (I paraphrase).

It will obviously take time for Russia to destroy those hardened layers of defense. This is what we've seen since their failed attempt to shock Ukraine into total surrender.

My opinion:

I think the winner will be the logistics winner. If Russia can continue until winter to kill Ukrainians at high rates as they have done for the last 2-3 months, it won't matter how much material comes from the West. There will be no trained Ukrainians to use it.

If Russia can consolidate their gains over winter while continuing to bomb and destroy incoming material and rebuilding efforts, 2023 will be a continuation of 2022.

If Russia's ammo and gun advantage ends there will be a stalemate at some point west of where they are now.

If Russia falls behind Ukraine in guns and ammo before Russia wipes out the vast majority of trained Ukrainian troops, then Ukraine has a chance.