In general, yes, you are wrong. I linked the wrong post in that thread in my reply. Please read this post, starting with the line “these problems are really only problems if you expect your disks to fail frequently” after the third quote.
Basically, you need to balance the lost escrow with the additional revenue potential of doubling your capacity. RAID1 gives you a revenue stream that is smaller but fluctuates less. Running a node per HDD will give you more revenue in the long run but you may see dips when a node fails.
If you expect your drives to last at least a year, RAID will cost you revenue.