Based on what? You certainly haven't given any indication of having read what historians have to say.
Granted, that subreddit could be a cabal of people colluding to make us think humans didn't go through a phase of drinking beer rather than water. It seems easier to believe you're trying to justify your own talking out of your ass if you can't respond to specific claims.
> In the old days, clean water was rare
What does this mean? Clean water was arguably much more common than it is today because of industrial contamination.
> What I do claim is that people did drink lots of beer for thirst in various contexts (listing exactly which would make this too long).
Nobody contests this. What is contested is fear of drinking water.
> I've worked on this for a decade, collecting archive accounts from around Europe. I can quote you pages and pages and pages and pages of people writing about how they used to drink beer against thirst every day.
Great! Pay up! I ain't reading your book.
Btw, you don't need metal to boil water. And beer is healthy if you're faced with a calorie deficit; it's loaded with nutrients. Perhaps you should use this as an argument for why people drank beer (allegedly and confusingly instead of water)
> I don't claim that people explicitly avoided water
Yes you did:
> And was this why people drank beer instead?
If you did not mean to imply that beer drinking came at the deficit of water drinking, you should consider rephrasing.
> What I do claim is that people did drink lots of beer for thirst in various contexts (listing exactly which would make this too long).
I have no doubt that someone in history said this, just as they did now; what I find hard to believe is that this was in any way normal or typical. One citation might be more meaningful than this entire thread. If you can provide a source, please do so.
Hell, I drink beer for thirst myself; against all rational judgement. This doesn't imply my tap water is unclean.