The thing that comes to my mind when reading over the last few pages is the phrase, "Go hard or go home".
Putin obviously failed with his 3 day SMO and has apparently recallibrated to going for control over his 4 new Russians oblasts to save face. Sadly I can see things going the same way as with Crimea and Donetsk/Luhansk, in that positions will be solidfied and defence lines reinforced. Then in 4-5 years time they will come back with another land grab.
As GDM rightly repeats, you simply cannot trust anything they say.
....And so it comes, I think, down to US/EU/UK to think whether they will just draw a line under the support given so far and it effectively have been "wasted" (As it has still resulted in almost 20% of UKR being occupied) or go they "go hard".
I really do think that those countries supporting Ukraine have to fully step up and realise that the only way that this will stop Putin's/Russias own Imperialist/expansionist ideas is to defeat them completely and kick them out of Ukraine. No more messing about with bits and pieces. Give them all those weapons that were going to be decommisioned, give them all the radar batteries required to close the skies, give them all that seized Russian money and also make sanctions bite harder. I also do think a total travel ban on all Russian citizens would have a huge impact.
Go hard or go home, stop messing the Ukrainians about.