I feel called out on the number of open tabs but hey gotta put that RAM to good use.
Seriously now, if I'm researching something the number of tabs just explodes to several hundreds. To be in line with the data hoarder principles I do save and organise the data so it's accessible offline but damn it can become quite annoying to manage at some point.
That's the thing, you could, but it wouldn't be best practice. At the end of the day the 3-2-1 rule applies to any data.
I know it's a hard pill to swallow, but ideally you'd need both a NAS (I'd go with Proxmox on a PC) and the tape backup for that NAS to ensure the safety of the data.
However. Backblaze may take the spot of the tapes - unsure if the NAS as well. Have a look at their offer and see what fits your budget. I would personally go with the NAS on site and backup it daily to Backblaze. Note that Backblaze B2 says something like 6$/TB/month which amounts to about 21600$/year which stings but then again it's safe and it's the best value (all the competition seems to be more expensive).