Will point out to you wackos that all casualty counts cannot even be done from satellite recon, for the obvious reason that bodies can be moved. Not to mention multi spectral sensors still have to deal with clouds.
The Russian estimates of Ukraine dead are almost certainly from artillery models, augmented by the occasional recon image that happened to be captured immediately after a strike.
Ukraine satellite recon has to come from the US, and coordination of spacecraft pass times with artillery strikes is much more cumbersome, because it goes through another country. So Ukraine’s estimates are from . . . likely imagination. They don’t have a historical database for artillery modeling.
Their generals did go to the same universities as the Russian generals, but those casualty models are much more recent than the 25 or so years since time at the Russian MTIs near Moscow.
Bottom line, Russia is using modeling. Which may be incorrect, but it’s a better reasoned method than imagination from Ukraine.
I think the Russian numbers of the Ukrainian losses in equipment come from the objective control, in manpower from the intelligence sources with access to the Ukrainian records.