Reasonable. A couple of things make the Russia watchers think its actually a concern for Vladdie.
The first is the antecedent of the Soviet war in Afghanistan which played a significant role in the downfall of the Soviet Union. The other is that he is actually manipulating mobilization to avoid big pulls from the two big metros of St Pete and Moscow specifically to avoid having those two populations impacted.
Russia's organizational military DNA is shambolic and chaotic only overcome by sending masses of men into the fray at huge costs. But, they do have breaking points. They did in WWI. The disasters can be put off by controlling the media narrative but social media appears to be much more open in post-Soviet Russia -- they run Telegram for example -- that people like Navalny have a relatively easy reach into the homes of the switched-on urban types.
The last item is the example of Prigozhin. His people are out there and angry about the casualties, the MOD's craptacular running of the War.