I think some of those issues probably stem from the fact that there's not really any alignment between the NVMe spec and the PCIe spec with respect to power management capabilities. I've encountered drives that have implicit dependencies where certain NVMe power management features only work as intended when certain PCIe power management features are available, but there's no way for the drive to express those requirements to the host system, and no standard compliance test suite that will reveal the broken behavior that can occur in the wild.

Sometimes figuring out who to blame for misbehaving hardware requires custom kernel patches, a hardware protocol analyzer at the M.2 slot, and reverse-engineering the motherboard firmware. Most of the entries in the quirks tables are based on a lot of guess-work and inferences because the kernel developers don't have the resources to fully investigate and reproduce these kinds of issues (and the hardware vendors simply don't care about thoroughly ironing out these bugs). It really sucks when you have to look at power flow out of the laptop battery and try to figure out from that whether your SSD is pulling more power than it should.