Not necessarily.

Roundabouts are used in area of moderate to high traffic where multiple roads meet and places where continuous flow is needed. Like motorway junctions. The junction near me is very high traffic, and we use a roundabout with traffic lights too. They can be less effective if the flow of traffic is heavy in one direction but not the other.

Traffic lights are used in busy urban areas where there are a lot of pedestrians or places with uneven traffic distribution. These can cause issues of slowing traffic in quieter times due to lights not really being smart and knowing when people are there.