All Russia seemingly want is for Ukraine to remain neutral and not join NATO or EU.
Why does Ukraine not simply agree to these demands?
If the only (realistic) options available to Ukraine are:
accept the demands and not be part of NATO/EU but otherwise continue to exist as a relatively prosperous nation with decent standards of living
refuse the demands, suffer from war, lose thousands of lives, and possibly be annexed by Russia or at least be ruled under Russian influence/control.
then it seems obvious that option 1 is preferable .... especially because option 2 STILL doesn't lead to them joining NATO/EU. So why don't they?