I have a Raspberry Pi running Pi-hole and Time Machine, making that little board probably the best value piece of tech I've ever owned. https://saschaeggi.medium.com/use-a-raspberry-pi-4-for-time-... is what I followed.
They’re more expensive, you need an extra RPi enclosure and power supply, you can’t use M.2 SSD sticks without an additional USB3 enclosure, they have a history of corrupting flash cards, and their idle power is only a little bit lower.
I did give it to my daughter to use at university but I very much doubt she actually used it and I've not thought about asking until this post :^)