Many retired athletes are unsponsored. Nearly every football and basketball player. All the ones you've never heard of anyway. Every retired cyclist. But I think this post misses the point twice.
First, I believe the OP meant currently active runners who are at a decent level.
Second, your list ironically includes some of the few retired pros that actually still do have a relationship with a sponsor.
Nearly every unsponsored elite athlete comes with baggage. Eric complained about not being accepted into the elite field at the NYC 5k and then got beat in the community race. Bad form.
If so, I think he has a decent argument as the best male runner without a sponsor in the country right now (outside of top collegiates like Hicks and Young, and even including them he may be better right now).
Liam Adams (2:10 marathoner, 24th at the Tokyo Olympic Marathon, 4th at Commonwealth Games Marathon) has been unsponsored for ages. He famously wears a hi-vis tradesman singlet and blacked-out vaporflys.
Sinead Diver - Not sure if she has some partial sponsorship with Nike, but definitely isn't a full-time deal. She has been told that she is too old for a full deal since she was 37. Since then she's gone on to finish 10th at the Olympic Games, place top 5 in a World Major and break the Australian record in the marathon.
Sam Parsons has recently confirmed he is not sponsored. But guessing still wearing Adidas gear based on him being on TME. Same everything but not getting paid anymore (after making the World's 5k final) has to be rough.