With Russia outgunning Ukraine’s artillery at an estimated 15-1 it looks like the main tool for halting Russia’s advance is about to start running at marginal effectiveness. Ukraine’s main industrial hubs are either already occupied, have incredibly difficult issues with supply lines, or have sustained physical damage, and artillery has been one of Ukraine’s most effective tools at slowing the Russian advance. The fact that Ukraine is simply using this ammunition faster than the west is willing to donate and faster than Ukraine’s domestic production can keep up with does not bode well for their ability to mount a meaningful defense for much longer. The last aid package passed by the US bought Ukraine only about 2 weeks worth of artillery shells.
To add to this, some of the decent militaries are also very small and designed to really to only be able to prosecute war while combined with the larger forces like Germany, France, and Britain. I have no doubt that the Austrian military is fairly competent and modernly equipped but as per wikipedia (grain of salt, I know) they only have 22,050 active and 160,000 reservists. Such an army would be deeply reliant on allied nations for air cover and intel.