I disagree. The RPi is a pretty versatile little machine. Yes, it does have some limitations, and the workarounds for those (like NVMe-over-USB) are not particularly optimal, but by sticking with RPi (rather than one of the other myriad SBCs), you get consistency and a reasonable expectation that the board is still going to be supported with an up-to-date userland 10 years from now.
I've been wanting to build a 4-bay SBC NAS for years now, but I haven't been able to bring myself to trust the community and support for some of the other boards that do give you direct access to the PCIe bus so you can actually get decent performance.
Now I'm waiting for someone to come up with something based on the Compute Module 4... (There was a post about someone designing a PCB for something that would do the trick the other day, but it requires some 0.4mm pitch soldering skills that I just don't have the equipment for.)