I agree with others that it's not cost-effective and it's a waste, both of your money and of the drives.
Buy one of those drives to use as your scratch drive for the files you're actively editing. For storage, use a NAS or a DAS - something like one of Synology's solutions, or a Drobo. Admittedly those have become fast enough that you could possibly run your active library off of one of those and not feel too much performance penalty, but it'll be fastest off of a NVME flash drive.
The benefit of a NAS (Synology or Drobo) or DAS (Drobo) storage unit is that you can pool storage and you're protected from one (or two, depending on how you configure it) drives failing. If the drive fails you can still work with your data, and recovering is as simple as pulling the dead drive and putting another one into its slot. It makes hard drives a "plug and play" peripheral. Just as an example, I also take tons of photos and video, and I purchased four 3 TB drives and then reused an old 1.5 TB drive that I had lying around. All together, it's a bit over 9 TB of storage; some space is lost to create that information to recover from one drive failing. When the time comes to upgrade, it's as simple as buying a larger-capacity drive(s), popping out the smallest drive, and then sliding the new drive in. The Drobo then spreads the data across the new drive on its own. You'd need to figure out how to migrate your data off of the drives, but you could theoretically reuse five or all six of the drives you mentioned in such an array (depending on which unit you purchased).
The downside to a NAS or DAS, particularly with a proprietary solution like Drobo does, is that you're stuck if the NAS or DAS experiences a failure. In most cases you can just buy a new one and migrate your drives over to that unit with no data loss, but I'm sure that if you hunt around you can find horror stories of total loss. In my case, I have my Drobo backed up online with Backblaze. That way, even if something happens to the unit and my drives (fire, flood, etc. in addition to the possible catastrophic failure of the Drobo dying and taking the drives with it), all I need to do is buy new ones and then re-download my data (or have Backblaze ship the data to me pre-loaded onto hard drives) and I'm all set. It's all pretty seamless in operation and doesn't require any input on my end. The cost is reasonable and in my mind it's worth it, as I have taken a lot of precious photos and videos that I wouldn't want to lose.
If you want more information about Drobo or Backblaze, I'd be happy to expand on it. I use Synology's router but not their NAS... but I've been impressed enough with their router that if and when I need a NAS I might choose Synology over Drobo.
