I think pushsquare are looking at the 7.5GB/s figure for PS5 SSD... which is why they think 980 Pro is needed, forgetting that the 7.5GB/s is compressed speed. PS5's ssd actual speed is 4.5GB/s (presumably read, or maybe both read/write) which several SSD's on the market can match.
We definitley need that compatibility list, however I imagine this is more of a "this will definitley work" list, and that SSD's not on the list will also work assuming they can provide good enough performance.
Cerny said in "The Road to PS5" that the storage you buy for the PS5 has to be a little faster than what's in the console to be able to make up for the extra stuff that they did for the PS5's internal storage. Start from 20:44 to 22:44 for what was said about it: https://www.youtube.com/watch?v=ph8LyNIT9sg
Sony, if you're reading this, do something new with The Legend of Dragoon. You will make me a happy man. Thanks.