Like most things, really. I used to build routers from old PCs, but eventually those tiny appliances caught up with the performance/functionality I need.
replyYou can do a lot of routing on a $70 Mikrotik, although they might not be "easy".
I really want to end up with one of these for at least a few months: https://mikrotik.com/product/rds2216
replyAt $2k out the door that's way more reasonable than I thought it'd be.
replyToo bad I can't fill it with old spinning rust.
For sure, it's a path and passage towards devices like that.
replyEveryone has a starting point, starting with soemone has lying around is one thing.. the quicker they can get going the more they can get to leveraging the real power in most devices.