I think Putin desperately needed it as Russia is starting to lose badly in Ukraine, not in terms of total available numbers of troops or ability to economically fight but just in terms of plain getting their ass kicked tactically and strategically in higher and higher percentages of engagements. Independent of the strategic situation, war is like tennis, no matter how far you are ahead in a game, you have to close the game out to win, which means winning points all the way to the end of the game. You can't just declare you have won because you have an obviously superior situation, and if the enemy knows every engagement you have with them costs you more than it costs them... well that quickly spirals into a massive problem no matter how far you are ahead because not even time will save you.

Whatever the reason, the big draw down in expensive anti-missile/drone stocks at least gives Russia a fighting chance (not that I am in favor of giving them a fighting chance here) but even still it doesn't matter as much any more if the US stops supporting Ukraine defense directly, it sucks but the effect seems to be Europe stepping up and investing in Ukraine and defense in general and I am not sure long term that is worse for Ukraine though short term it is obviously not good.

Particularly in the political realm of war, the new way to do a high profile military response that doesn't accomplish a military objective are drone attacks on cities that make big headlines but do little actual damage to the war machine of a country at level that matters enough to turn the tide of a war. This isn't to say the violence and destruction they cause isn't real, but rather it is aimed at almost more of a pyschological violence against a population of civilians rather than a material attack on a vulnerable part of the military industrial complex of Ukraine that facilitates it's ability to fight. If Ukraine has decisive missile defenses however and can embarassingly shoot down all of Russia's drones, that actually becomes a serious political threat to the legitimacy of their military in terms of the global world's assumed mantra that Russia must be overwhelmingly more powerful than Ukraine in sophistication and number because the saber rattling just looks weak.

I am not super confident in this, but it may be an indicator of how desperate Putin is getting, to push wildly for a drawn down of antimissile systems available to Ukraine so that Putin can manipulate a PR path to save face and lose the war in Ukraine while claiming to win because even as the logistics and infantry (armor? no more of that for Russia in any strategic number) mostly withdraw the world news can keep covering shocking massive drone attacks on Ukranian cities and retain an air of inveitability to Russia's dominance.

This isn't to say Russia isn't dangerous to Ukraine anymore, but rather to underscore that they are getting desperate.