Overhead telephone and cable TV lines are common in North America.
Modern fiber optic telephone cable has the advantage that it can be strung next to power lines without interference.
In heavily populated regions of the UK, the only overhead cable that would be visible is the telephone line.
The lesser populated regions of the UK, the countryside for example, will have overhead power cables.
Although it is safer to keep the cables underground, it would be difficult to repair a line if a fault were to develop.