I don't see myself buying a Synology again.
I didn't want to use mine as 'just a NAS' and was hoping the Linux+ssh they ship would allow that, but it hasn't gone as I had in mind. Certain things I wanted require jumping through weird extra hoops, and system decisions I don't particularly agree with are just imposed. The toolchain generally seems quite dated, the kernel is from 2017 (v4.4.59+) and to me their proprietary package format (.spk) seems pointless given we already had apt-get/etc. I saw back in December they deprecated DDSM, also DSM7 was delayed, still not out and that was before Corona so who knows now.
If you wanted the option to spin down your disks, sorry, it's evidently impossible b/c Synology requires you to use their partition layout which dumps their OS partition onto all your data disks.
My needs are low write/high read & I would have preferred installing the OS on a dedicated SSD. In fact I paid extra for a '+' Syno with SSD slots, but whoops, too bad the slots can't be used for a bootable OS because there's no BIOS. So something, probably log file appends for services I don't care about are why my data disks spinning 24/7. Maybe that's good for Syno's support costs but it's not great for me.
Why not install Ubuntu you might ask? Sorry, not possible == no BIOS.
I know plenty of people love their Synos -- if it works for you, great. Just one guy's opinion. If you need a NAS for 'just' file serving then you might well be OK.
But if you want to do anything beyond the surface, I suggest looking elsewhere.