My homelab has been running for 20 years, during which I've gone through something like a dozen desktop and laptop PCs. Copying a terabyte of media to each of those computers seems like a terrible waste. My TVs, either through Raspberry Pi or their own software, can also play all of that media.

The homelab also runs a few 24/7 services that do stuff overnight (most notably sensor data logging), pihole, routing, media management. It's lower power than the desktop/gaminng computer, and it's not practical to have those 24/7 services on a laptop that leaves the house periodically.

So, homelab to minimize the amount of storage replication, minimize power consumption, and provide always-on processing.

Of course, having that platform, it's also an opportunity to play. Implement services that totally wouldn't be practical in and of themselves, but setup makes a fun diversion for an afternoon or a weekend. Remote access for the rare occasion when I'm traveling. Monitoring the otherwise invisible, headless computers. (like NUT to keep track of 3 different UPSes)