I don’t know any serious leftist who would assume once we have a socialist system we are just done
It's what Marxism is about isn't it? Leftism is heavily influenced by Marxism, you hear leftists often say "late stage capitalism" without thinking how stupid the implications of that phrase are. Constant references to Star Trek abound, without realizing that show is actually agnostic on economics, they use an ideal system, but the writers don't know what that would be. "Post-scarcity economy" is another phrase that's used often.
Overall this indicates leftists don't actually know anything about economics, they're just unhappy with how things are going and have no idea how to fix it. Not significantly different than the MAGA movement, just putting faith into narratives that feel right to them.
I think at this point we're just buying time to diversify trade. It's incredibly stupid to to think factories can be built in two weeks or even that businesses can source products from suppliers in other countries in that time frame. This is seemingly what Trump thinks, but yeah, it's stupid.
So I'm hoping they're doing everything needed to end dependence on the US in the background while mitigating the impact of Trump's nonsense in the short term. But as @sbv@sh.itjust.works says, we can't really know we're just reading tea leaves.