The way I see it is this: Les Stroud (Survivorman) takes the same stance as you do here, if it's fresh, clear, and flowing it's most likely safe to drink. That said, the man has also gotten giardia multiple times in his life for that attitude and whilst it's a very unlikely, would you want to be the guy that lost out on $500,000 for not doing something so basic and well known?
Like packing clothes specifically with a mind to destroy them for resources, which has been one of the more interesting elements of the show imo. And boats. I had no idea boats would take off as such a big thing, who the hell aspires to build a boat in these situations and succeeds? Skillful insanity.
There was a winner without a sleeping bag? What was considered more important?
Around here I take my chances as not boiling water is the daily reality and has been for hundreds of years. In locations I don't know as well I would be more hesitant. Boiling water might be basic, but it isn't free. It takes time, effort, firewood. And it adds some risks of its own connected to that. People have left Alone from burning down their shelters, fish hooks, falling, axe and knife injuries and so on. There is a risk and cost to everything, as well as an upside by doing or not doing. (Or to the extent or quality you do it). As you say I don't want to be the guy going home for not boiling bad water. Equally though I don't want to be the guy going home for chopping myself in the leg while getting firewood to boil perfectly fine water.. Realistically I think I would try to balance the extra work with boiling water against the perceived risk at a location while also having in mind any extra risk due to chopping more wood and doing more fires inside. Certainly a point worth thinking carefully about though, and that didn't even cross my mind as a potential issue before.
I think that is one of the more interesting parts of the show. How the "free" items can be made or used for more tasks. Totally agree on the boats - impressive! Not sure of the actual success rate though? Some of the shelters have been quite impressive too, but some seemed to have taken too much energy to build.
I remember one woman would use a waterproof boot to collect water from the lake and bring it to the shelter.
I really enjoy seeing campcrafts, the chairs, cups, games etc. things to improve quality of life and tackle the mind game. Sadly, however, the editors often glance over that and we instead just see a guy drinking from a cup whilst an onscreen text says 'X made this cup on day Y.' There was one guy that made a foot-operated faucet for his sink and created a whole american-football board game, then quite because he missed his partner. A shame, that dude was not only inventive, he was thriving.