Off TV was only thing that realy worked with the WiiU gamepad, the asymetric gameplay was barely used, and in some case did more harm than good (Starfox)

So, I for one, thinks that's good we got rid of asymetric gameplay.

You can not lose something you never had. The Switch never had two screens.
So you lose nothing. But you do gain a handheld when you buy the next Nintendo console, so that is cool.

I agree the dock shouldn't exist unless it has some kind of function we don't yet know about. There could also have been ways for it to just stream footage to your tv.

I kind of wish it did do dual screen play. I think there was a lot of untapped potential there. That being said, it would make no financial or practical sense, except to appeal to Wii U fans... of which there are few.

^This.

the function of the dock, is to dock the switch...

Connect it to the TV, while charging the system, the reason they made it so big is that they wanted it to hide the screen, they didn't wanted to be clear about the switch being an one screen console only.

And whys nots?

I don't understand your question, try to be more precise.

This is actually a good thing. Wii U costed more and had to split some of its power to stream to 2 screens at once. This allows the switch to not compromise itself in any areas and to keep costs down a bit. Dual screen gaming is better for 3ds as both screens are attached to the same console and, I believe at least, doesn't compromise itself nor up its cost as much. 

you can play with joy cons also, dont?