Since SSDs require no seek time, and retrieve information much faster, Cerny said that the PS5 targets a load rate of 5.5 GB/s. In theory, that’s almost 10 times faster than the PS4.
Then again how often do you trust the tech writer department.
1) Reality check: Samsung 970 PRO has 3500MB/s sequential read and costs USD$169 for 1TB.
What, you want even faster? Samsung PM1733 goes up to 8GB/s using PCIe 4.0 * 8 lanes. In other words, the same bandwidth needed as your PCIe 3.0 16x graphics card. That's why the Samsung 970 Pro above is a realistic example of real life performance using PCIe Gen 3 * 4 lane, which has a bandwidth of 3940MB/s
2) 10 times faster than PS4? 5.5GB/s divide by 10 = 550MB/s. No HDD in the world has that speed. And that speed coincidentally is the same speed as a SATA SSD after it maxed out the SATA interface. And PS4 never came with SATA SSD although you can upgrade it to one.
Hence the 5.5GB/s load rate is likely a misunderstanding. Even if the SSD can handle sequential, it is unlikely to handle it at 4k IOPS. Plus, CPU has to do work during load, too.
Considering point 2), the possible guesses are:
a) Interface speed, which is attainable. PCIe gen3 x4 lanes is 3940MB/s, bump it to gen4 and you get around 8GB/s. However, a 5.5GB/s number doesn't really make sense here.
b) Some stupid target number because some guy said "10x faster than PS4's SATA interface".