Zelensky should have inquired about NATO guarantees before sending half his country into the meat grinder. The only guarantee NATO gives is a knife in the back. Ask the Kurds about it.
Ukraine didn't take peace deals throughout the war because they thought the Europeans and Americans had their backs, and would let them into NATO for security in the future.
Now the Ukrainians have lost hundreds of thousands of people, huge tracts of land, and are about to be looted so hard it will make the looting of Russia after the dissolution of the USSR look like a cake walk.
The Ukrainians fought for a lie. Rule no. 1 of geopolitics. NEVER trust the Europeans or Americans. They will always backstab you.
NATO (Stoltenberg) proudly rejected Putin's offer to avoid the war by refusing to ever admit Ukraine. Was evil war from the start, and was never intended to end well for Ukraine.