Russian military journalist Dmitry Steshin in an interview talks about a story from 2015 when Russian army tried to capture Ukrainian town of Mariinka near Donetsk. This interview is interesting in that Steshin mentions two topic which Russians previously carefully avoided but now they are becoming much more relaxed about. Firstly, Steshin mentions "advisors, you know who, those who weren't there", clearly referring to regular Russian army who was deployed into Donbas between 2014 and 2022. Putin fiercely denied their presence but evidence was so overwhelming that in military circles in Russia everyone treated this as a tongue in a cheek joke on his side and everyone laughed at some Western experts who seriously talked about some "pro-Russian guerilla fighters" who seemed to have infinite human, military and financial resources for a decade, including the latest Russian weapons. Russians even made a special neologism ихтамнет (literally "those who are not there") to refer to these people and that's whom Steshin is referring to.
The second important fact Steshin mentions is the tactics of Russian artillery in preparation to siege of Mariinka - six hours long artillery barrage on the town during which out of 400 intended targets only 0.5 were actually hit. It's unclear whether he means 0.5% or "half of a target" but it doesn't really matter, as it clearly demonstrates how indiscriminate the Russian shelling was. But since the town was still populated, the Russian shells still landed somewhere and they usually did so on civilian residents houses, resulting in significant destruction of the town and civilian casualties. Please keep that in mind when Russian propaganda once again speaks of "shelling Donbas for ten years" and resulting casualties, because vast majority of them were caused by Russian's own indiscriminate tactics.