I have ADHD, not autism, but this is something I hear a lot, and I think this is a mischaracterization of what these conditions are and how they impact daily life. Most mental illnesses/disorders/etc aren't just defined by unique and niche symptoms, but also by issues most people have experienced, but cranked up to 100 and present all the time.

Take depression for example: we've all felt sad at some point, and maybe even had times where we had low motivation and felt empty due to grief or stress, but if these struggles are permanent and all-consuming to the point where you struggle with life, you may have a disorder.

Some of the things listed in the image make sense when done in response to a certain stimulus, or in a specific context. But if you're living your entire life in this way, something is clearly off-center.

There's also a lot of overlap with symptoms between different disorders, but understanding the source of these behaviors can be crucial in learning how to deal with them. Just because 'hiding ones feelings' isn't unique to autism, that doesn't make it less unhealthy.

Right, lots of people have felt depressed too. That doesn't mean they've got clinical depression. It is clinical when it is so extreme that it impacts every facet of your life.

Think of it this way: lots of people can't see well, but not seeing well doesn't mean blind. If you don't see well you can improve your life by wearing glasses. If you're blind glasses aren't going to help. The whole way life functions revolves around dealing with being blind. There are all sorts of things you'll need to do to cope with blindness that people who aren't blind, or simply don't see well, don't have to do or think about. So it isn't quite right to equate not seeing well to blindness, even if people who don't see well can imagine what not seeing at all might be like since they can partially experience not being able to see.