Phones don't have DualSense features. But admittedly a good grip would probably be cheaper than $199.99 for a phone. 

 Stuff that just drains the battery so fast to the point of being usless.

Can I play on this while my wife games on her account off the same ps5?

No. 

The use case for this is:

- playing on your PS5 while someone else uses the TV with a different device. 

- playing on your PS5 while you're out of the house but still connected to wifi. 

No. It's like a Wii U gamepad.

Pass. Makes it almost as useless as the Steam Deck for me.

No streaming of PS+ games and its recommended for playing at home when "Someone else needs to use the TV" is so dumb.

The Playstation 5 isn't powerful enough to run two instances of a high-end AAA game.

There might be the potential for some Multi-player, but this is strictly a streaming device that is a substitute for the TV at this stage.

Pass. I get the intent but no.

Yeah I realised not long after posting , the processing power that would be needed. 

i don't see how there is a big enough market for this thing. Why bother. 

Why would a Steam Deck be less useful to you?

Literally thousands of your Steam games are compatible and could be played anywhere, without dependency on another device or internet connection.

If that ain't enough, you could also play lots of other PC games (DRM free or via other launchers) on it, without dependency on another device or internet connection.

If that ain't enough, you could also emulate thousands of other games on it, without dependency on another device or internet connection.

If that ain't enough, you could also stream games over different game streaming apps/services as long as you have a decent internet connection (doesn't have to be your own Wifi area).