The trouble is that it is behind your security perimeter once it is on your home network. It can start discovering other devices, monitoring traffic, enumerating ports and services, etc.
If you're set up for it, you can always set it up on a sandboxed SSID with access only to the internet (or even just to sites you choose, like an FTP server of your ebooks). This is probably a good idea with most sketchy gadgets that "need" access to the "internet" but will probably be off the table in coming years as it gets cheap enough for manufacturers to embed 5g connectivity if they want.
Sounds like a lot of work when the alternative is just using a device that doesn’t spy on you in the first place. For instance, Remarkable is a great e—ink tablet that literally gives you the keys to the kingdom: there’s a UI in the product that gives you the root PW (which is set randomly for each device).
Does remarkable have a web browser or email support? I don’t use chrome so it will be hard to add reader articles. Mostly I want to add them from twitter on ios.