They could be better and given the limitations, I think they do the job. If you don't like them they offer the pro controller. But there have been times (especially when flying) that I have used them detached when not docked.
I honestly don't think the Switch would have succeeded the way it did if the controllers were always attached, forcing you to buy another controller for when you wanted to dock.
That's if we're ignoring the absurd drift their sticks have that Nintendo has seemingly never fixed. I hope to god they fixed them in this next gen console.
I needed to repair one pair last year because the drift was unbearable; the repair costs almost as much as a new one. (And one started drifting again.)
I am not a heavy player at all and I got the drift.
But the execution in the Switch 1 is flawed. They're on the small side, and generally fiddly. If the joycons for the Switch 2 are larger and just more ergonomic then I think it'll be a win.
EDIT: the joycons also being little motion wands was also quite good. You don't need a separate accessory like on the other consoles. Overall the joycon is a neat little package of functionality, if imperfect.
I mostly play with either a Switch Pro Controller or an 8BitDo (that is actually my favorite).
I have large hands and the joycons are a little uncomfortable for me. But it makes sense, they should feel great in the hands of a child.
And I mean, if you have kids, being able to double your controllers when they have friends around is also helpful to avoid arguments.
The detachable controllers were pretty magical, modulo the reliability problems.
For portable play, yes, the stick drift issues suck, but Nintendo will fix it for you. And yeah, most portable systems today overall just have better analog sticks.
But if I'm at home I'm going to be using a Pro controller or an 8bitdo or something like that.
As others have said, their primary issue is with quality control around stick drift.
I'm not a gamer, but the original Switch joycons always struck me as overly complicated and expensive. It should be cheaper to manufacture and sell Switches with the controllers attached. Indeed, this is what they did with the Switch Lite. For games that take advantage of joycon functionality, Nintendo could have sold something like an updated Switch version of the Wiimote as an optional accessory.
Do users who are happy with their Nintendo Switch have a favorable opinion of the joycons, or would you be happy without them?