The reserved subnet for RFC2544 is specifically for “benchmark testing”, and what is a homelab for if not for testing, including, but not limited to network benchmarking. (In fact, after reading this specification I’m interested in actually adding my own network benchmark numbers as well some day.) This range has absolutely zero chance of ever having a conflict with any VPN of any kind, and it also won’t overlap with many of the devices that default to 192.168.1.0/24.
What’s also cool about this is that you get two /16 subnets out of this, which works so well when emulating an air-gapped infrastructure:
Did I mention that it is also a lot easier to include on documentation and whiteboards?
Related: