Those aren't an equivalent solution at all. A NAS is for storage of lots of data, even the biggest options from the companies you mentioned wouldn't provide as much data as I have on my NAS. If I were to host the data in a real solution for larger amounts of data such as with Backblaze I'd have to pay nearly $1000/year.

There are multiple different tiers of data that I keep: on device, encrypted snapshots, cloud, and NAS. There is differing amounts of money and effort I'm willing to spend depending on the type of data, but no one solutions is sufficient for everything.