It is a reasonable assumption given he said "raid 10". By "cheap" I mean all spinning disks. Enterprise SSDs are an order of magnitude more expensive than the best spinning platters. ~$25k for 3TB.
Raid 10 basically just gives performance over Raid 1. You might Raid 1 SSDs but Raid 10 is likely to be a very expensive way to hit your IO bus limits.
Given that, assuming it is spinning disk is a reasonable assumption, and the accusation of a strawman was unnecessarily rude.
I don't find it to be unnecessarily rude. It was a legitimate critique of the poster's own assumptions. I guess that because I'm not an HN "insider" I'm not allowed to challenge someone's assumptions. Only once you hit the magical karma level are you able to do such things.
