Haven't seen morton's neuroma mentioned. It's a possibility. Runners, particularly mountain runners, frequently have it. Progresses from tingly, "nervy" pain to "hot spot" pain to numbness. I've had it off and on, though never numbness in the big toe; mostly 2nd to 3rd toes. I find that numbness tends to occur after running on alpine rocks. Sometimes taping the toes together (big toe to second and second to third) helps "splay" them out and relieve the pain. I know some folks cut a little "donut" out of foam and tape that around it. (Put the donut around the trigger point and then tape the donut in place.) Or get shoes with bigger toeboxes or cushioning (Hokas). Mine just went away with time and apparently adaptation to that running style.
Again, I don't know if this is the answer, but it's a possibility I didn't see mentioned.
Again, I don't know if this is the answer, but it's a possibility I didn't see mentioned.