The important thing about drone warfare campaigns is that they are only successful if the enemy is unwilling to challenge your air supremacy over your own territory.
This is the case in Ukraine right now and in the Nagorno-Karabakh conflict. Russia is unwilling, right now, to challenge all of Ukrainian airspace, and Armenia/Russia was unwilling to challenge Azerbaijani airspace.
The moment this change is when the drone strategy is no longer effective. Drones only work when you have air supremacy over at least a staging area. When you do not, then there is not much to do.
Also, Russia has it's own drones, which they are not using because they are in the defensive position right now.
If there is a prompt for a Russian advancement or if the line becomes untenable, the drone-based strategies will collapse and the conflict will turn unless Ukraine can muster up something else. Simply put, Ukraine has no hope at all of contesting air supremacy with Russia. It's air force is incomparably worse, and drones have no anti-air capacity.
But we are not there. Russia is nowhere near attempting a full-scale invasion and hasn't, they limited themselves to taking the Donbass and Crimea and defending it strictly, more or less.
As for Russia in Armenia, there was not really any cake-on-the-face. Russia's policy was to stand-by unless Azerbaijan was threatening Armenia proper. Maybe Armenia could have negotiated another arrangement had their orientation been different, but as it stood Russia was unwilling to do much at all in the NK conflict.
As it stands the balance of power is still overwhelmingly in the favor of Russia and it is not close.