By "tethering" I am referring to the tecnique where the internet connection of a phone is transferred to a PC through e.g. an USB cable. Now, this is quite questionable due to how most modern phones are filled with proprietary software and freedom violations, yet tethering is quite easy to do even on blobless distros such as Hyperbola and pre-Bookworm Debian, and in my case tethering did not require any blobs to be installed on the target computer. I don't own a phone and I don't trust phones at all, I am merely using tethering as a temporary and admitedly  questionable solution until I can find a better and more freedom-friendly way to achieve an Internet connection on a recently-adquired old laptop, so my question is:

Is using USB tethering as problematic as e.g. getting an Internet connection by installing a proprietary driver on the PC (such as ath10k)? Could the proprietary software/firmware of the phone "spread" to the target PC during USB tethering and cause it to behave in a way that goes against the wishes of the PC's user, or are there enough security precautions that should keep the unethical firmware unable to damage the target PC?

If my concerns about USB tethering turn out to be true, then maybe it would be a good idea for libre systems like Hyperbola to recommend against tethering, otherwise people might be lead astray since since tethering is so easy to do and may give a false sense of freedom/security as (atleast in my case) it doesn't require installing proprietary drivers on the target PC. If my concerns about USB tethering turn out to be FALSE, then discard my suggestion.