Then sounds like Apple put some really garbage SSDs in the 2020 Intel-based Air, not sure what you're looking for here?

But 2-3x won't change swap from grinding to a halt to perfectly smooth, either. It's still over 20x slower than RAM.

More significant for swap usage though is random reads and read latency, neither of which are going to be particularly impressive on the M1's SSDs. You need something like Optane to make that a compelling case.