I call this effect Forum Induced Anxiety (FIA).
Common in most all forums, as people tend to post problems to gain attention, as few want to see 100 posts that their Tesla's are performing great.
There are also a ton of investors on the short side of the stock. It is not unusual for them to post false complaints, hoping to lower stock prices for their own personal gain (the brokes suspension saga)
Enjoy your Tesla. Take the negative forum posts with a grain of salt, but also to learn from.
Indeed, it is just human nature and the motivator of a negative experience that produces a stronger emotional response. What I mean by this is that people are more motivated to publicly announce an issue and generate discussion if they had a bad experience or something is wrong. They are motivated either by a desire to "warn" prospective buyers or owners and/or punish a company for a perceived wrong. I myself have felt this desire and have acted on it in cases I felt strong about my case.
That said, it is easy to look through forums and blogs and conclude, holy cow -- how does a single Tesla make it out of the factory without falling apart ???
It takes some self discipline to realize that what you read is not a statistical representation of the product's population and you can see this phenomena in many products not just Tesla or cars, but in phones, computers, etc. etc. That is not to write off people who have publicized problems, these are often helpful in seeing future issues, but it all should be weighed accordingly.
I have more or less stopped caring about restaurant reviews that get 2 or 3 stars, as I read through some commments -- "oh, the food was great but my waiter was 5 minutes late getting me a glass of water to I will give it one star, it really pisses me off"....
EDIT: I do want to point out though, many of the common complaints you see about MX are real though... for example, creaky falcon wing doors (FWD) is real, easy fix, but definitely a buggy design and quality issue, or door latches getting stuck. I still love the car, but it would be wrong to simply dismiss some of these common issues as anything other than Tesla needs to implement a few fixes to make the product better. Model S went through this as well but as it has been in production over 5 years now, most of the production bugs have been worked out. The nice thing about Tesla is they do honor all the warranty work, so little issues get fixed. For me, as an example, my driver's side door had a paint drip in the center of it, under the clear coat. The second row passenger side seat belt buckle did not function properly, and the seat adjust switch was non functional.... all was fixed promptly without charge. Another common issue with MX is the A/C, often develops leaks and needs to be fixed, sometimes at the most inopportune times.