It’s as meaningless as any words that hang on the notion that there’s a “spectrum”.
You either you accept what works and fosters human well being and liberty, adjusting your politics accordingly to reality as we learn more about the world, or you’re conservative, a fundementally irrational denial of reality.
This is why seemingly different groups like Marxists and neo-nazis end up at the same place ultimately; they’re unwilling to give up on failed ideas. It doesn’t matter what label one applies, if you’re still trying failed ideas after they’ve produced untold amounts of harm then you’re just on one road to fascism or another.