Though it's true that the anti-GMO and even anti-Nuclear sentiments I see accross the spectrum but those differ a bit from conspiracy theories in that it stems from junk science, rather than a belief in a hidden government or group wanting to personally change you.
Just google for outbreaks in the US that are linked to anti-vaxxing and take a note of their locations. Most will start in heavily left-leaning areas. To clarify my point, I personally believe that anti-vaxxing is about evenly distributed between left and right wing, just for different reasons.
P.S. As I was trying to find an article about an outbreak in Seattle that I remembered from a few years ago, I realized there is another one happening right this moment https://www.seattletimes.com/seattle-news/an-anti-vaccinatio...
Unless you mean things you don't like are conspiracy theories in which case we might as well just call everything a conspiracy.
I seems to me that 'The Patriarchy' / 'The Privileged' on the left are conceptually quite similar to 'The Deep State' or 'The Jews' on the right. And those are most often described as conspiracy theories, and rightly so.
The difference between a conspiracy theory and a social critique is the personal nature of it. People that believe that the 'Jews' or that 'The Deep State' is responsible for everything believe that there are specific actors, people doing things explicitly to stop someone.
When people complain about the patriarchy or systemic racism they're complaining about a large tangled of social contracts and norms that result in certain people, races, genders etc being disenfranchised. For example it's a statistical fact that a black man smoking marijuana is not only more likely to be thrown in jail but also more likely to face harsher sentences than a white man smoking marijuana. What else would you call this, other than systemic racism?
You can't point to a similar statistic, study or what not that shows 'The Deep State' is specifically targeting Donald Trump or that 'The Jews' are attempting to kill all white people. You can, however, point to specific actions and trends the FBI has taken in the past to disenfranchise black people, including actions taken against Martin Luther King Jr.
One side explicitly has a factual basis behind it. The other does not. That's what makes one a conspiracy theory, and the other something worthy of scrutiny.
It usually gets more personal at the extreme. People will show you stats that shows a disproportionate majority of federal employees supporting the Democratic party and infer that there is 'systemic bias', some will point at specific cases and make leaders of hidden conspiracy out of them. I've seen enough of 'Kill All Cops' to know that there is similar extremes on the left.
Yes, there are going to be people that will take anything to an extreme. That does not make 'Systemic Racism' somehow a conspiracy theory, especially on the level of things like the 'Deep State'. Arguing otherwise is to me the highest delusion.
Unless you can give me examples of conspiracy theories and their peddlers on level of Alex Jones for the far left.