The article isn't talking about the size of raw disk blocks, better called the sector size. It's talking about ZFS blocks, which are variable in size, defaulting to 128 kB: https://en.wikipedia.org/wiki/ZFS#Variable_block_sizes

ZFS aside, the 512 byte sector isn't even a hard limit at the storage medium level. Disks with 528 byte sectors — and other odd sizes — have been available in the enterprise world for a long time now: https://en.wikipedia.org/wiki/Hard_disk_drive#Market_segment...

HDDs and SSDs with 4 kB sectors dominate the consumer market now: https://en.wikipedia.org/wiki/Advanced_Format