Whey protein for runners

Whey protein isn't the magic silver bullet that the Protein companies would lead you to believe. It's just a convenient way of boosting your daily protein intake. Many people see benefits from using it as their overall protein intake was too low beforehand but it's no different to getting your protein from any other high protein food.

A lot of them comes very sweetened, and when blended with milk and a frozen banana, they make kick-ass milk shakes.. that's one "benefit" :)

You don't need any protein shake garbage.

All you need is a healthy diet and good balance of electrolytes like potassium, sodium, chloride, magnesium, etc.And being on the ketogenic diet will help to deliver more oxygen to the cells as result better overall performance.

Overall protein intake is what matters - there's a gram per kg equation for endurance athletes, which I can't remember (I think it's 1.7g per kg of bodyweight).

As a cyclist, I supplement but tend to add it to my porridge/ overnight oats, and mix with yogurt. Rarely I'd have just a shake tbh, as all the stuff about timing has limited support, especially if you're not doing two sessions a day.

I recommend healthy diet. That's all you need for a good life cycle.

Since carbs are none essential, why not?

Cutting out an entire macronutrient from your diet is unnecessary and over the top. Considering when all the OP asked about was getting extra protein.

And given you don't know what level of exercise they do, you don't know to what degree carbs are 'non-essential'