It is much, much easier than it used to be. The documentation and videos alone available make something like this a very welcoming learning experience that anyone can complete step by step by pausing a video and replaying it.
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.
You can do a lot of routing on a $70 Mikrotik, although they might not be "easy".
For sure, it's a path and passage towards devices like that.
Everyone 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.