For stuff like this it's wise to look the other way internet forum hype is pointing. Enthusiasts and tinkerers are over represented on internet and not representable for the general population. To be a bit mean I would almost say that 3 900 000 of those 4 million steam decks went to tech YouTubers that drove an incredible hype around launch. 

As for "traditional" console byers: traditional consoles don't come with a games compatibility list and fiddling with settings to make "almost" compatible games work. They just "work" (as long as the game was released for that console).

With that said Steam Deck is great for what it is (just to big in my opinion). But it's not for me, games I would want to play through steam that I don't get on console is usually stuff where I want keyboard and mouse.

To think that some companies like Square Enix goes the extra mile to make their games Steam deck verified based on this numbers, Valve just keeps winning, even when they do low selling stuff like the Steam deck companies can't help themselves to do everything Valve wants them to do. While other more succesful systems like the Switch get skipped all the time, and i expect the Switch 2 will also be skipped all the time by the companies rushing to ''Steam deck verify'' their games.

I just use my steam deck as desktop. I watch family guy and Frasier on it and do Uni work. Its pretty great if you want to get away from windows and don't have much linux experience and technical background.

Interesting, I only see the figures going up a good amount over time. It's clear Nintendo will continue to dominate handhelds and they're actually a console, not PC.
From a selection bias perspective, I actually have two people in my family (in two separate households) that have a Steam Deck. That's quite a bit for something that has only sold around 4 million units.
I've not seriously considered a Steam Deck or any of its competitors because I have a lot of consoles, and I want Switch 2.

Things can be tricky like that, like I knew more people that had an Xbox than a PS2 and more people that had a Wii U than a PS4, despite the sales being massively the other way around. This is why anecdotal evidence carries little empirical weight.

I always found those arguments on the internet & from nerdy Twitter users so silly. 

The Steam Deck was revealed around the time the Switch Oled was revealed at 350$ with no spec upgrades, along with other Nintendo controversies at the time with 60$ remasters & NSO being a rip-off. So it was easy for impulsive Twitter users to unnecessarily bash Nintendo and praise the Steamdeck as the thing that will destroy the Switch, not realizing that nerdy spec Twiiter users probably encompass less than 1% of the Switch's market. There's far more that goes into the appeal of a game console more than specs, their arguments were delusional from the beginning.

I also notice that many of the people who were bashing on the Switch/Nintendo fir being underpowered and only 50$ less than a Steam Deck were the same ones who purchased a Switch and wouldn't even purchase a Steam Deck. 

I don't at all hate the Steam Deck and I do think it's great for it's niche, but people acting like this was destroying the Switch is silly. The Switch will always be more appealing for it's exclusive games, seemless options to play on the TV & Go, cheaper price, marketing, ect...

On a gaming laptop the games are also not clocked offline. So why would this be a better option?

I can do other non-gaming processes like with email, Word, finances, etc

Also emulation without having to go through hoops since any laptop I get will be Windows based.

But...thats exactly the reason why I said I was avoiding getting a laptop as well.

I can do all of that on my iPhone (non-gaming processes and emulation) and for gaming wise, I have my Switch.

When it comes to PC gaming, I'll play on my gaming desktop since I prefer higher resolutions and higher frame rates - and to experience all that on a bigger screen.

Good sales for devices with basically no marketing and retail presence.

I got three PC handhelds this far (Steam Deck, ROG Ally, Legion Go) and while I enjoy tinkering around with them, I have one major problem with all of them: they are not really portable. The devices are so massive that you can only carry them around in a backpack. You don't feel like taking them out on a 20 min bus ride or something and most of the time, I don't bother to give up that much space in my luggage even when I'm travelling for longer. So the handhelds actually are just something for the bedroom. The abysmal battery life also adds to my impression that Steam Deck and others are half-portable at best.

The Switch on the other hand is light and somewhat small. The Switch lite even fits into my pocket and is more like what I expect from a true handheld. I don't know how much all this affects sales. But I sure do know that it lead to me still playing mostly on Switch. I'm kinda worried about the Switch 2 getting bigger. I hope it will still fit into my laptop bag that I'm carrying around. Wouldn't want to carry an extra bag just for a console.