Bearing in mind that this is my personal opinion, and my comments are of a general nature rather than drilling down into a specific subset... lets open the flood gates.
Some of that perceived nastiness comes from the various stages and knowledge levels of vaping - in particular, the egos that drive that knowledge... or lack of knowledge. Beyond the more technical and user knowledge levels, we can include age, education and even levels of responsibility and integrity.
New vapors are new vapors. Unless they happen to be electrical or mechanical engineer types, they don't know much, save but what they are told. What they are offered may be kindness with a understanding of their limits - what they are told may be accurate and useful, or... complete BS.
Like most enthusiast pass-times, there is a hive mind mentality... with fiction entering the hive mind almost as easily as well supported fact.
At one time, there weren't near the options there are now... and there were less variables on the table.
There weren't near the number of B&M and internet "experts". At one time, sub-ohm was fairly rare for anyone that wasn't using an RDA. Mechs (not much else had any real power) were mostly high voltage drop crap... or due to limited runs and better quality control, ridiculously over-priced and not in the budget of anyone less that totally dedicated.
Now... we have layers upon layers of variables. There are threads I don't participate in, because they concern a niche I don't care to participate in.
Hundreds if not thousands of atomizer variations. Regulated and unregulated. Sub 20 watts, to and 300 watts or more. Reputable and disreputable vendors... all wanting a piece of the ever expanding pie.
Finally... like the joke about the internet in general. A kind, generous, thoughtful and well considered positive comment is becoming a rare and unique unicorn. The bigger the forum, the more room for mean spirited and stupid people to participate. Forums that take the step of allowing foul (adult) language... may (unthinkingly) encourage it's use.
In reference to some other, unnamed forums...
Where foul language is allowed... without a facial expression or context to consider - along with poor grammar, weak composition and annoying text message abbreviations... the potential for misunderstanding, responses "in kind" and rapid escalation of tensions... is high.
OK... felt good. Won't make a difference... but felt good.