Comment by sliken

Maybe you want to configure 4 nodes to provide redundant network service.

Or experiment with VLANs, firewalls, QOS, and related. Sure transcoding multiple 4k video streams is intensive, but there's plenty to be learned about performance, networking, configuration management, DNS, fallover, network storage, rolling upgrades, SSL certs, VPN endpoints, and 100 other network services that run easily on today's SBCs.

Plenty to be learned with a handful of cheap linux boxes and even a RPI5 or RK3588 is quite capable. Sure not state of the art today, but home lab != hyperscaler, but just might help get you are job at one.