It's not just about if Russia can manage without Europe/USA, it's about Europe managing without Russia.
So ok, China and India actively supports and essentially bankrolls Russias colonization strategy and this might show as growth. So in short, it's possible for Putin to rearrange his business, sell oil below market price, and show growth, but in the long run its not a viable solution to run a country on.
Add to this the cost of war and loss of manpower. 3-400 000 might seem like a small amount of people when Russia has a population of 147 000 000. But it's not. It's Russia slowly slowly depleating their civilian workforce in a situation where Russia has a declining birth rate with 2023 being the lowest since 2014.
So if shit was going so great, Russian salaries would have skyrocketed and Russia would have their top model tanks on the battlefield but none of that is happening. Instead we see a lot of weird shit from the former Soviet Union on the battlefield. Add to this that back in October there were a lot of press about Russians having less money for necessities than anytime in the last 5 years.
So while Putin has seen no change in quality of life, rest assured that the average Russian has less money to spend on necessities.
Remember: Putin and his friends has been peddling the "everything is A-okay"-bullshit for over a year now but it's just propaganda. Even though there might be periods where Russian economy looks like it's going great it's just not true for the long perspective.
When you get chemo it kills both ordinary cells and cancer cells. However, the body is normally capable of producing more cells than a tumor which means that with enough time more tumor than body will disappear.
While we hurt, Russia hurts more and that's a good thing.