I don't think that people in general have a problem with "techies" or "nerds". They do, however, have a problem with people who are generally referred to as "hipsters" today.
It is understandable why the dislike is there. Hipsters do tend to exhibit an attitude, behavior, fashion sense and materialism that can easily been seen as socially obnoxious.
Residents of long-established neighborhoods, especially those made of working-class individuals and families, will not be pleased when their neighborhoods are invaded by hipsters. The resulting changes to the community can be quite rapid and painful for those already there, both economically and socially. It's not about jealousy, but instead about unwanted disruption of established communities.
To some extent, the traditional "techie"/"nerd" community has been similarly co-opted by hipsters. This is especially true with Apple's resurgence over the past decade, when it comes to social media, and in SV in particular.
There was never this much strife when the tech industry was made up mostly of "techies"/"nerds", who in general behave in a way that is more socially friendly to established communities. Now that the balance has shifted toward hipsters being more and more prevalent within the industry, it's perfectly understandable why there's more hatred toward the industry as a whole. Their way of life invokes a very negative reaction out of basically everybody else.