I agree that we should engage with reality as it currently exists. Davyd Arakhamia [1] is a Ukrainian member of parliament, in Zelensky's party. He was one of the negotiators early on with Russia. He stated that Russia's main demand was simply that Ukraine agree to not join NATO. Meduza has an article about it (which also links to the interview itself) here, as well as spin from various sides. [2] If you're unaware of the source Meduza is to Russia as MSNBC is to the Republican party. Here's his quote:
---
"They actually hoped until nearly the last moment that they could press us into signing this agreement, adopting neutrality. That was their biggest priority. They were willing to end the war if we took on neutrality, like Finland once did, and gave assurances that we wouldn’t join NATO. That was essentially the main point. Everything else was cosmetic and political embellishments about ‘denazification,’ the Russian-speaking population, blah blah blah"
---
He goes on to elaborate that the main reason they didn't agree to such is because (1) they didn't trust Russia and (2) Boris Johnson told them they should "just fight." And maybe Russia would have "really" invaded with the sort of logic you put forth in your post later on, but that was clearly not their goal in this invasion. Not joining NATO is hardly some Hitler level appeasement as our propaganda spins it.
Russia was paranoid about NATO, which has gradually been working to surround it with nuclear weapons, having a base setup in Ukraine which has a geographically clear path straight into Russia's heartland. And I don't find such paranoia particularly unreasonable. Countries that strongly turn against America tend to find death and destruction at their doorstep soon enough.
And none of this is to justify Russia's invasion, nor condemn Ukraine's decision to fight. Rather I emphasize that we live in a world that's a million shades of gray, even if propaganda from one side or the other invariably frame it as the clearest thing ever. And enough people will believe such unquestionably, ensuring war will be with us til our final days.
[1] - https://en.wikipedia.org/wiki/Davyd_Arakhamia
[1] - https://meduza.io/en/feature/2023/11/28/we-had-to-buy-time