Yet helping crackpots (along with every other motivated people) find each other is unavoidably part of what the Internet does. I believe the good coming out of it outweighs the bad, but you're definitely not the only one being afraid.

It seems that many of those scared are those who've learned in a time of knowledge scarcity (it was difficult to find any information at all on any subject. It took at least a trip to a library and some ability to search the index). Today the challenge is to critically navigate in an overdose of information, a lot of it complete rubbish. The hard part is about filtering out, not finding material.

Now what scares me is that, at least in my country, many teachers haven't realised that the times of knowledge scarcity are gone. They tell student that using Wikipedia is cheating, instead of teaching them how to understand and navigate its (wonderful) citation system, to properly assess information quality.

(note: I suspect your comment to be tongue-in-cheek, but I felt like interpreting it 1st degree anyway)

I was only half tongue-in-cheek. I'm not really that worried about obvious crackpots having an effect directly. It is entirely plausible though that they could have an indirect effect. If banded together they could reach more of the public with crackpot ideas, and even if the public generally recognizes these ideas as crackpot, they will have succeeded in shifting the Overton window, enabling public acceptance of less obvious crackpot theories.

I am worried though about the (further) rise of anti-intellectualism and anti-science. The effects of this should be pretty clear just by reading the news. This does worry me more than the concerns you've described.

If one were to look at my Facebook feed at any random time and imagine it representative, one would come away with the impression that vaccines are an evil plot by pharmaceutical companies to make money, that airplane contrails a.k.a. chemtrails are an unknown but surely nefarious conspiracy by the government involving mass quantities of psychoactive chemicals dumped into the air, that "natural" healing using tea and crystals and such is way more effective than doctors and hospitals and pharmaceuticals, and plenty more along those lines.

My mother is deeply into this stuff, and I have some friends through her who are lovely people aside from the part where they believe in this stuff. They don't make up a large proportion of my Facebook friends, but some of them are very loud about their beliefs.

Now imagine if you don't care a whole lot about this stuff one way or another, you get your shots on schedule because that's what people do, you never considered government conspiracies because the news never mentioned them, and you see the doctor when you get too sick because that's what everybody does. Then you become exposed to all this stuff, written very confidently and seeming to be backed up with solid facts, charismatic people, and high production values.

I think there's a good chance you'd start believing it!

See also the Freemen on the land who pass incoherent legal information on to each other.

(American readers may be more familiar with the similar "Sovereign Citizen movement": https://en.wikipedia.org/wiki/Sovereign_citizen_movement)

For a good example of such a case:

http://captainranty.com/freeman-shafted-by-clueless-judge-2/

...I got halfway through that before realising that the author was actually serious rather than using snark!

Most people like that really just need someone to talk to, so introducing them to eachother solves both their issues neatly