That alone doesn't cut war crime definition to get attention to ICC and isn't really different from the usual aerial bombing. You drop the bomb from a plane or 100 of them somewhere around the densely populated area and don't know who they kill, as there is no connection to the drone.

Civilians dying in an armed conflict doesn't cut the definition of warcrime by itself. Deliberate targeting and intentional destruction of civil infrastructure that supports life or something like it is.

Then of course there is stuff that ICC isn't getting busy about which is clearly above the threshold -- the regular drone safaris in and around Kherson (city with pre-war population circa quarter million people) happening for the last few years.