>>>This is like assuming that cancer is good? More cells, better body?
There are many things in our build up, where evolution have been outcome from viruses. However I do not like your comparision to cancer - cancerous cells are generally shredding cells from the unity of your organism - they might be making new organism, but that organism is not part of your evolution anymore. Changes that are happening in autistic brains are not destroying brains, but is part of the processes that are changing and optimizing them for the environment they have to exist in and the reasons for those changes are evolutionary - those changes started long time ago. Do you like that or not or can it be worded better - it does not really matter here.
>>>This is just a hypothetical counter-argument. More connectivity could be better, "more intelligent", and autism seems to be "cool" among nerds for this reason. But maybe it's just a fallacy, just a way to pretend to be something better.
You might be new. The mainstream argument and a direction for autistic people where it was going for a very long time has been, that autistic people were mentally disabled(not only intellectual but also emotional), which clearly is not the case. I mean, yes - that attitude might be helpful for purposes to suck out government support, but that leaves autistic people treated like deficient people, that are not contributing to society and telling a talented and intelligent person, that he is mentally disturbed would yield different results than telling that the person is very intelligent. And frankly, the issue is not hypothetical, like you have classified it but autistic people that they are smarter(at some things) stands out in the crowd. Genius and NT at this point in time is oxymoron.
>>>Yesterday I listened to a podcast episode about bird brains [0]. That some birds have a way more efficient brain than ours, even if they are not as intelligent as we are. They are smarter than other primates, but their brain just weighs around 10g, while the one of chimps, which are about as intelligent as some birds, weighs 400g and consumes a lot more energy. They have an underdeveloped cortex, so apparently it isn't as important as one might think. That it could be that the cortex is more dedicated to sensing, than to thinking. Birds, for example, don't have such complex sensory inputs like our hands or our entire skin surface, that "memory mapping" all those inputs requires such a big cortex.
You seem to have somewhat lack of knowledge and mixing things together based on what you know. Bird brains also have "cortex" - they have evolved some parts of brains, that are important to their evolution while we have massivelly developed cerebral cortex even compared to other primates, which is not what you are comparing here. Primates are much more inteligent than birds and if you realy want to go the route of comparing brain size, which you have got wrong, then brain weight to body mass comparision in birds is much lower than that to primates. As for energy that is used to operate brain, I would really need to know what is the evidence of that claim that birds are smarter than primates. It is assumed, that higher energy consumption of brains is because of amount of calculations that are happening in brains and birds brains are no more efficient than human brains - you can't use ostriches as a replacement of a very simple tasks for programming, that even dumb student can do.
The issue that you have declared that cortex is not needed is that it does not change the fact, that the cortex as part of human brains is not going to go away - cerebral cortex have developed over long time and it seems to be going to be foundation for future developments of human brains and also autistic brains. We could even get larger cerebral cortex, but expecting that some other brain regions would develop more than they are(as they also are constantly changing), compared to cerebral cortex is going against the topic, as while there are some changes in other parts of brains, the ones that are in celebral parts are more important to brains of austistic people.
We have wasted so much time in getting over your nonsense, but the information flow of human eyes is massive - the "thinking", that brains are doing is basically in discarding most of information for later processing. Autistic people have overflow of that information because their brains are not behaving "normaly"(like other human brains) and are not discarding as much information as other human brains does but tries to process it all. That is very much evolutionary change and very clearly processing more information has advantages compared to those that does not have them. Generally the things that some people are freaking about overstimulation will go away, as it is part of how changes are happening, but changes that will wire brains differently are there to stay - for all humans eventually.