Not the greatest take.
I take my steam deck with me everywhere. Whip it out in the drive thru if the line is too long, on any plane or car ride, start gaming at a friend's house while I wait for everyone to wake up and get breakfast after a night of partying.
To claim it isn't portable because you can't fit a power bank in the default case is a little short sighted. There are plenty of travel cases like MVRPDXC that are small enough to reasonably by carried around anywhere and everywhere, sort of like a purse for gaming.
I've taken my deck with my on hikes, out of the country, literally everywhere. This article is reminiscent of a lot of similar posts I've seen on Reddit.
And in my opinion, it seems like the only people who are disappointed in the steam deck are people who never take it anywhere (hence defeating the purpose of owning a portable PC). And it makes sense that you would be disappointed, though it doesn't make as much sense that you wouldn't, you know, start traveling more with it.