Multiple drives of a lower (1-2tb) capacity might be more expensive, but they’d technically be more resistant to a single failure over fewer larger (4tb+) drives when in a pool/array.
Multiple drives of a lower (1-2tb) capacity might be more expensive, but they’d technically be more resistant to a single failure over fewer larger (4tb+) drives when in a pool/array.
More drives also equals larger power consumption so you would need a larger battery backup.
It also means more components prone to failure which increases your chance of losing data. More drives means more moving parts and electrical connections including data and power cables, backplanes, and generated heat that you need to cool down.
I’d be more concerned over how many failures you’re seeing that makes you think smaller drives would be the better option? I have historically used old drives from ebay or manufacturer refurbs, and even the worst of those have been reliable enough to only have to replace drives once every year or two. With RAID6 or raidz2 you should be plenty secure during a rebuild to prevent data loss. I wouldn’t consider using a lot of little drives unless it’s the only option I had or if someone gave them away for free.