The recently published Healthy Streets score card results. unfortunately show Sutton ranked near the bottom of Inner/Outer London boroughs.
Overall
Below shows the 2021 figures.

LTNs
When we look at Low Traffic Neighbourhoods unfortunately we fall further down the score card.

There are some though.
We can see from the Safe cycling in London Google map that these pre-existing ones give us the 0.01 score.

Reducing traffic to achieve the declared Climate Emergency objectives of carbon zero in 9 years time will need some more!