If you take a look at how storage is billed in cloud, you'll see a huge difference. Networked storage, e.g., EBS, provides durability and survives VM restart. But it is billed on IOPS. 200K IOPS is a piece of cake for today's NVMe. But a 200K EBS easily costs you thousands per month. High-end NVMe devices, unfortunately, are all instance-level storage, which means they are gone if you shutdown your VM.