Yea, but, like owning a car you soup up in your garage, it isn't about what you _need_, it's about what's fun and what's enough to give you something to do in your free time.
It should be obvious to the reader that this is very much overkill, even for the stated goals of expandability and learning.
Incidentally, this setup does leave me some significant headroom in terms of compute resources, but that's by design.
If it's inference, don't expect great performance or cost-effectiveness.
But if you learn a lot during it, I wish you all the best!
If the goal is to have a lot of something so you can play with many different things, this gets the job done. If the goal is high performance and maximum efficiency for learning or compute, a setup with dozens of smaller computers like this is usually not the optimal choice.