Yes true if they lack appropriate air support and logistics support. Which is the case for Ukraine.
Modern western strategy is very different from that of WW2. The key is integration of air support, artillery, armor, infantry, etc. If Ukraine had superior fighter jets, to gain air superiority and anti tank and anti personnel platforms like A10 and Apache, all platforms working in sync and all backed by logistics support to keep everything operating, it would be a different story I guess.
Related, I wonder if they’re suggesting the old Russian tanks would somehow perform better than the western ones? Because as far as I know, western tanks have the best armor systems, the highest accuracy, and the ability to fire while moving. Maybe they need to adapt their tactics to make better use of their platforms?