In an Insurance Journal article, insurance expert Bill Wilson addresses this question. Since automobile insurance policies do not define "pedestrian" the answer is complicated.
Personal auto policies, and commercial policies with uninsured/underinsured motorist and personal injury protection will cover injuries to a "pedestrian". The question is whether a person in a wheelchair, on a bicycle/tricycle, skateboard or horseback is a pedestrian or whether they literally have to be on foot.
Some statutes do define "pedestrian" in a broader sense, but they do not directly address auto insurance. Courts often refer to the dictionary which gives a narrow meaning, but some have found the word ambiguous. Having a policy definition could clear this up.