ALL BluRay plays ------you won't be able to play the newest discs.
I don't do that.
BluRay player sat unpowered / disconnected for about a year then removed it from the media shelf along with the old DVD player.
With DirecTV, its not only firmware updates, but DirecTV has a steaming feature where you can watch programs from the start via an Internet connection. With DirecTV, you also can watch TV on iPads and iPhones in your house, and you can even download programs to these devices for off-network viewing. All these features don't work without an Internet connection.
So yeah, you can leave the Internet disconnected, but you lose lots of other features in the process.
Firmware updates still can be pushed via the data / media stream. I don't watch TV on iPads or any tablet or any phone (tablets - phones are off in the house). I do save programs for watching on tablet / phone / carpc sometimes but not much as I am not a TV watcher. I have used my tablet on international Skype calls to the EU or Pacific Rim while waiting for a change of oil in my automobile. In to satellite here having multiple BUD's in the 80's and then DTV when first introduced. Only now that AT&T owns it I am considering switching over to DISH (which I have had concurrent to DTV over the years).
I can stream live TV on my tablet just fine when I want to but never do (via HDHomerun tuners).
I had Tivo a while ago and switched over to DTV DVR which is not plugged in to the internet and works just fine.
Basically use the Internet for myself; maybe selfishly? I am typing this message now using my CC ISP connection.