I'm pretty libertarian as well, but this stuff bugs the crap out of me, because of your "harm to others" comment. The overly-cautious are generally the ones demanding that liberty be taken from others. Let me provide an example...
I live in a wooded, suburban community outside of Washington DC. There are ~50 miles of paved and unpaved trails through the woods maintained by the monster HOA.
A significant # of people walk alone through the woods or ride their bikes alone on the streets with masks. Many will walk without a mask, but quickly pull their mask up within 15' of passing someone at about a 6' gap on the trail. There is not a single bit of medical efficacy in doing this.
Now, I don't care what people do, and certainly there may be a small percentage of people who are immuno-compromised and take extreme precaution, but there are far too many doing this to be limited to medical necessity.
Why it bothers me, is that the behavior of wearing masks in ridiculous circumstances is endemic of a certain broader COVID-policy view that hurts our kids and hurts society through other economic and medical repercussions.
Healthy people who wear a mask in the woods are generally the ones demanding that outdoor dining be banned, even though there is almost no transmission outdoors at all. They are the ones who say that vaccinated teachers cannot return to schools to teach healthy children who have almost zero risk of even experiencing symptoms from COVID. They are the ones who are retired or have white-collar, work from home jobs, who demand other people with minimal to almost zero risk be prevented, through the force of govt, from supporting their own families. As a liberty-minded individual, I detest the "overly cautious," not because I care what they do, but because they generally are the ones seeking to limit the liberty of others.