A couple of cases I’ve found you can use if you want to build your own NAS.
Jonsbo N1
You have seen this, Wendell used it in a video. 5 3.5 disks and 1 2.5, mini-itx.
Jonsbo N2
A cube version of the N1. Also 5 3.5 disks and 1 2.5, mini-itx.
I’ve also found a couple of no-name NAS cases on AliExpress that are sold under a couple of different brands. 4-8 hot-swappable sata drives. The smaller ones do mini-itx and the 8 drive version can do mATX. A downside of these are that they use 1U power supplies which can be a bit noisy, or flex atx power supplies that can be a bit pricy.
The company ZhenLoong makes hot-swappable sata or sas hard drive cages for dual or tripple 5.25 bays, but they also make this case I think is kind of snazzy. It has 9x 5.25 bays in the front so with their drive cages it can do 15 3.5 sata or 12 3.5 sas disks. It’s a full tower case so it can do up to EATX. It’s basically a vertical 4U case. A bit pricy though and just the shipping is $250 since it’s big and heavy.
(This case would be perfect for @wendell to put 9 dvd drives in and rip the entire world.)