Not even for streaming. But for general "safety while on the Internet" when the devices (Mac, iPhone) are mostly on public or not-so-secure WiFi (at the residence or on the go). Plan is to keep it always ON or almost always ON.
Not necessarily for the UK.
(Other than Mullvad)
It took me all of 10 minutes to set up.
The static IP address, recorded by every site you visit, is directly linked back to you personally, and only you.