There’s a lot of space in the left that isn’t stalinism. You can be a communist and have a deep critique of how 20th century communism worked, a learning from it and not wanting to repeat the bad parts.
In leftist circles in the US, weird Stalin and Lenin fans are loud, but ultimately not that common.
“well actually” room temperature superconductors do exist, quite definitely! … But only at 100 gigapascals of pressure. https://uspex-team.org/static/file/Troyan2022_ufn227g_High-temperature superconductivity in hydrides.pdf
Still really cool, but not useful for engineering.
I agree that this paper needs to be replicated before we get excited.