This has me thinking. I wonder if it's the case because they're working with otherwise healthy people who are willing to try anything to get better, and there are many sports where operating in ketosis gives better performance.

Also they're not as targeted by advertisers on the anti meat, anti fat side

I guess I don't follow all that many of them, I have seen cardiac specialists, GPs, molecular biologists, endocrinologists

One of my favourite youtube channels is Low Carb Downunder which is videos almost entirely from conferences where many different sorts of researchers present their research on LCHF diets.

In a broad sense, dfferent medical specialties draw doctors with different personalities.

Sports Medicine doctors are often put in situations where they are DEMANDED to improve performance, i.e. attached to sports teams. I think this sets them up as a group who is naturally looking to experiment and find a edge

The second biggest group are the obesity specialists (ex Westman). I think for similar reasons.