Yep. Definitely need to consider your use-case to determine whether or not the Steam Deck is for you.
I think maybe my situation is the opposite of yours. Initially I was kind of hesitant and unsure of my purchase. I even waited a few hours after learning about it before I finally decided to just pre-order it with the understanding that I would have some time to make up my mind later on whether or not I really wanted it. Even earlier in this thread I had stated that I was in no hurry to to get it. But the more I think about it and the more I hear about it, the more I think that Q3 can't come soon enough for me.
In my case, I don't often go far, or for long, but even if/when I do, the Nintendo Switch (or 3DS before it) only gives me maybe 3-5 hours of battery. So I pretty much always need to have a charging source anyway. That said, I rarely travel by plane, and I usually get carsick if I try to read or play a handheld in the car, so I'd likely only be playing in a hotel (or similar) room, with an adequate power source nearby, rather than while in motion on the road.
Also, it's sometimes fun to have a "LAN" party with Nintendo handhelds, which in the past 15 years or so I've always done somewhere plugged into a power source because the batteries have been so short lived. So I can see myself doing something similar with the Deck. But the Deck has the added advantage that not everyone will need the same console/handheld hardware, or have to lug a huge desktop PC around, or own an expensive gaming laptop. And with Remote Play Together we won't even necessarily need multiple copies of the same game!
And while my PC is still generally decent, I built it in 2011 (2nd Gen Core i7) and it hasn't really been upgraded since then, other than some increased/replaced storage (HDD/SSD) and a few years ago the fan on my aging GPU died (again, after having already been replaced by the manufacturer) so I got a used GPU (GTX 670) which I think made its debut in around 2012.
Basically, given how technology has improved in the past decade, I think the Deck should be at least as powerful as--if not more powerful than--my current computer. So I'm hoping this will be a modest upgrade for me at a minimum. But even if my current PC runs something better than the Deck does, I can still use Remote Play to run the game on my PC in the home office while it streams to the Deck (which could be connected to my TV).
As implied, my PC is a desktop machine. I don't have a laptop. So having the portability of the Deck, and the (assumed) affordability of the official dock, or at the very least affordable 3rd party USB hub, means I should be able to have multiple docks to easily transition from one room/screen to another as I see fit. And I can even use it as an emulator and get a console-like experience from it to enjoy some "
oldies but goldies" by myself or with others.
(I can't tell you how many times I've wanted to have multiple docks for my Nintendo Switch so I could easily move it from one room/screen to another and back again. But Nintendo's official dock is sold for $90(!) and there have been many reports of 3rd party docks bricking (or otherwise damaging) the Switch, so I've never bothered to get a second one. Which means any time I want to connect it to another screen I need to disconnect and reconnect the power source and display cables. And after doing that enough times I just sometimes don't feel like it anymore which means often my Switch remains powered off when otherwise I might be inclined to use it.)
As things stand now, I think it's quite possible that the Deck will be my "daily driver" computer, if I can learn to live without Windows most of the time. That may be a bit of a stretch, but I'm excited to get my hands on one and find out.