You are aware that, as of 2021, both Ukraine and almost the entire international community considers Ukraine's borders to be everything that it had pre-2014, right? So, if one is proposing that the Russia be entitled control of Crimea, Donetsk and Lugansk, that is not factually "nothing".... that's a significant concession.
Either way, your hypothetical elides what was discussed above, the absolute barest of bare minimum concessions that should be required of the Russian government: the recognition that Ukraine has a right to exist and self determination. Vladimir Putin, at the outset of the war, declared that they didn't. Until there's a signal on that barest of bare minimums, why would Ukraine be interested in negotiating with them?