Plenty of capitalist countries collapse, every single human society has collapsed sooner or later. You're living in a collapsing society right now. The actual question is how well the country manages to meet the needs of its population while the system works, and USSR did a far better job meeting the needs of its people than capitalists states today can manage. USSR eliminated things like homelessness, and ensured everyone had their basic needs met. This is evidently an impossible task under capitalism. And of course, today China is the biggest growing economy that's lifted over a billion people out of poverty. One has to be an utter ignoramus to think that communism does not work.

Meanwhile, communism is an economic tool just the same way capitalism is, however it's pretty obvious that both economic systems require an ideology to function. The nordic model is the best example of Europeans plundering the rest of the world to subsidize their lifestyle.