You're misreading the article. Its subject is that because of the way IO stacks have been built CPUs are becoming the bottleneck in IO, this is an issue for both network and non-volatile storage IO e.g.

> a 40 GbE NIC can receive a cache line sized packet every 5 ns, but the last level cache (LLC) access latency is already up to 15 ns, which means a single LLC access can already prevent the OS from keeping up with arriving packets

and

> NVMe SSDs perform I/O faster than the OS can accept new (asynchronous) I/O requests and notify their completion.

They also note e.g. that while nvme provides for 65k command queues OS generally have one IO queue per CPU.