Even after passing the 80m units, the Nintendo Switch still doesn't have streaming apps like Amazon Prime or Netflix, even though the WiiU (and even the Wii and the 3DS) had some of them. Why? They are seemingly everywhere nowadays, and it's weird to see such a popular hardware without them.

Didn't they state something to the effect that with the switch they were concentrating on being a gaming device and that customers already had a multitude of devices to stream content on. Can't say as I agree but that is one less vector of attack for hackers and one less thing they have to keep updated.

But that would mean Nintendo said no to those apps to the Switch, which would be weird, since that could bring bad press to the console ("Nintendo forbids companies from bringing services to the console" kind of bad press). Why would Nintendo say no to other companies developing sevices like those? Seems like nothing that Nintendo should bother about.

Gamepass is a direct competitor to Nintendo, services like Youtube, Netflix or Amazon Prime are not. Not really the same.

More services and flexibility for their hardware? I get that the focus of the Switch is gaming, which is what it should be, but I'm somewhat annoyed with the lack of QoL elements and services that have become ubiquitous on it. Again, it's not a big deal, but consoles really should have more features than their predecessors, not less.

I don't know that they have said "no" to it.  I just don't think they've actively pursued it.  Hulu and YouTube are both available on Switch.  I have a Hulu account, but I almost never use it on Switch since there is a Hulu button right on my TV remote.  Accessing the app through an additional external is redundant and unnecessary.  Same goes for Netflix, Amazon Prime, etc.  With the proliferation of Smart TV's, there's less need for consoles to be used for these features.  You shouldn't need your video game console to be running all the time if your aren't playing games on it.

That's a fair point, but again, the Switch wouldn't lose anything for having more features, even if they are redundant. In that sense I would have to agree with @The_Yoda, since preventing a possible doorway to piracy may be worth sacrificing some features. But then again, nowadays a console is going to get hacked no matter what, so I'm not sure if the rewards would compensate the losses.

Because it is a video game system, not a media box.

How many laptops, desktops, smart tvs, phones, tablets, and video game systems do you need in one house that all play the same apps? It simply isn't a useful use of their time/effort/money to accommodate these things on the Switch. Nobody is buying less Switch games or not buying a Switch because it doesn't have the same apps they already can conveniently use on probably multiple things they own.

Although I doubt it figures in there is the fact that: If you are using other devices to stream you are avoiding wear on your system's battery and other components. This means less replacement units sold but would also add a certain value to the perception of the devices longevity. I know how much Nintendo values customer perception (i.e. software rarely going on sale to be perceived as always being worth more) and again although I doubt what I postulated is the case, it is possible this idea was floated and gained some traction.

I’m really glad it doesn’t have any of these services. It’s the simplest game system I’ve ever had the pleasure of using, and as far as I’m concerned, the less clutter, the better. I love the direction Nintendo are going in.