The internet providers offer their great IP boxes. I saw that at a customer’s place, an expensive OLED is mounted on the wall and needs such a great set-top box. But then only one device can be operated, so extra costs for a second set-top box.
Satellite system on the roof must be grounded, for existing buildings it’s always a topic how to get the cable to the equipotential bonding. No grounding needs to be provided on the wall from 1m upwards. However, if it is planned over a conservatory, access then is a great thing (I have experienced that).
But I would definitely install a satellite system and not just buy it at Bauhaus or Amazon. Most of the time it just looks stupid afterwards.