As a member of NATO, I can see Ukraine provoking Russia...(with Ukrainians living in Russia) and forcing NATO to defend Ukraine.
I can see that as well.
I personally don’t think Ukraine has to join NATO.
The problem is, I think Russia thinks they are owed eastern Europe. Not just because they owned it during the cold war, but because of the extents of the Russian Empire before WW1.
Many wars were started by aggressors who claimed to be the victim and used being attacked as a pretense, such as Hitler claiming that Poland invaded/crossed Germany’s border in 1939.
If they want to have an ‘ironclad’ agreement, it has to be ironclad about zero tolerance for hostilities, no matter what the pretext.