Yeah, the joycons are gonna suck as standalone controllers. There are still advantages to removeable controls, though.
1. It allows the Switch to function as a standalone tablet, If Nintendo is smart enough to include a proper browser, Youtube,Netlflix support, and a low power mode for inproved battery during non gaming tasks, can see this replacing my Android Tablet for most uses.
2. The removeable controllers will make it easier to fit into a purse, bookbag, or even large pants pockets.
3. It theoretically means the joycons in there current form could be replaced with a different design down the line.
4. Smash Bros has a tendency to ruin joysticks. It would be incredibly shortsighted of them to put that game on a handheld with non-replaceable controls. Replacing a joy-con will be as simple as sliding out the old one and putting in the new. That alone is enough justification for the added cost, if you ask me.