We had pretty smart weapon systems for a while now! P-700 Granit and Brimstone missiles were doing cooperative engagement and target selection for decades. BONUS rounds fit target recognition into small pucks. If we squint just a bit, many naval mines, especially something like CAPTOR, are "vehicles that can identify and change targets fully autonomously".
AI is not the limiting factor as much as sensors, energy, datalinks, logistics, and costs are. Yes we can miniaturise TERCOM now, but then where would the vehicle get maps from (battlefields change!), how would it see the terrain (at night? on a foggy, rainy day? deliberately dazzled/blinded with a cheap laser?), how far can it travel, how much payload can it take, where does it launch from, and how does it get to the launch point? Working through those questions and anticipating cycles of adaptation, I think it's easy to end up with a $1m JASSM-ER or a $3k 155mm shell (neither of which Ukrainians have in sufficient numbers).
For example, if you know there's an enemy platoon in that forest, why would you fly a swarm of autonomous tree-avoiding hunter drones there if you can drop some 155mm instead? The enemy can't blind a 155mm shell, EW wouldn't work, shells don't care about fog or darkness, payload-to-weight ratio is ~100%, and they're cheap. Of course if you don't have shells you have to be creative, but that doesn't mean the creative solutions are better.
On the other hand, according to the episode I linked, humble unarmed non-AI DJI Mavics have a very persistent and systemic impact. They provide 24/7 eyes in the sky over the entire front line, which makes tactical surprise impossible. This is very much not "AI swarming slaughterbots" many seem to imagine and invisible to folks on the sidelines like us, but that's why I'd be cautious of making inferences from the media we get to see.