Edit: I wrote about that setup and other Linux/PCIe root complex topology issues I hit back in 2021:
I think your test had 10 980 Pros, which were probably around $120 each at the time (~$1200 total). SSDs are wildly more expensive now, but even if you spend $500 each, it's nowhere close to EBS.
It's apples vs oranges, but sometimes you just want fruit.