Why didn't Ukraine and NATO simply pretend to agree to Russia's demands? [closed]

Russia have invaded Ukraine to prevent their admission into NATO. Prior to the invasion, Russia made it clear that they wanted assurances that this would not happen.

Why didn't NATO and Ukraine just agree to these demands to avoid invasion? Note I am NOT saying that NATO and Ukraine should've actually decided to never let Ukraine into NATO. I am saying why didn't they just pretend they wouldn't, to appease Russia and avoid invasion?

Instead, what we got was Jens Stoltenberg, NATO secretary general, completely shutting down these requests by Russia, saying things such as ,

It's only Ukraine and 30 NATO allies that decide when Ukraine is ready to join NATO. Russia has no veto, Russia has no say, and Russia has no right to establish a sphere of influence to try to control their neighbors. Source.

I just don't understand how this was considered a smart move politically, it's just seems like an astonishingly naive approach. Why provoke Russia in such a way? Why disregard their threats of this being a "red line" issue? Why not be savvy and simply pretend that NATO has no intentions of admitting Ukraine, but, of course, behind the scenes, you can still do whatever you want.... and then all you need to do is wait for the opportune moment to make it public, and at that point, there's nothing Russia can do, since the planing of an invasion would take time, and in that time, NATO could easily establish a no-fly zone, as well as sending NATO forces into Ukraine.