For reference, the slower speed seems to be around 1500 MB/s read and write, compared to 3000 MB/s read speeds for the M1 MBP [0]. While there are definitely applications that would benefit from the extra speed, I wouldn't call 1500 MB/s - ~2.5x the speed of the fastest SATA SSDs - a "performance issue."

[0] https://www.macrumors.com/2022/06/26/base-m2-13-inch-macbook...