but the compression is a software thing right? thats not specific to a SSD or HDD
I thought there was some specific hardware to handle that (both on Series X and PS5)
The SSD can deliver uncompressed data to other system components at up to 5.5GB/sec via its new proprietary hardware, which is over twice that of an Xbox Series X. And like the Xbox Series X, the PS5 also has dedicated hardware-based decompression to reduce CPU overhead.
Read more: https://www.tweaktown.com/news/71340/understanding-the-ps5s-ssd-deep-dive-into-next-gen-storage-tech/index.html
Sure any game on PC can (and does) use compressed data as well, and the superior CPU on PCs likely handles it just as fast. On the consoles it won't effect the CPU at all. (or very little) The big difference is delivery, straight to where it needs to go on ps5 instead of multiple steps.
Anyway fast travel can finally be fast travel, not wait a full minute for the world to reload.