Their war equipment is not "last-gen", they basically keep upgrading whatever was left of the USSR and they do sit on the huge stocks of non-modernized Soviet equipment, but eventually they will be left with a useless old and vulnerable hardware. Yes, they made some next-gen tanks and planes which are not combat ready yet but modern Russian industrial capability would be able to churn out only token numbers of those anyway, under sanctions and brain drain.
Russian equipment loss in this war won't be replaced for decades if not longer.
Russian equipment loss in this war won't be replaced for decades if not longer.