Not to deny your friends experience, but just to shed light on an issue common with chronic illnesses:
People naturally heal all the time from illnesses like this. They just get better with time.
People also get desperate (and sometimes their doctors) and try all manner of remedy.
You get a situation where people who naturally recover end up attributing that recovery to whatever random remedy they were trying at the time. This can be compounded by having bands of people who got sick around the same time, tried whatever flavor of the month remedy was talked about at the time, and recovered around the same time.
Having long covid myself since summer 2020, I've watched this play out more times than I can count now.