I don't lose my hopes for this, also because right now we read only rumors: there is nothing set in stone.
Remote play can't sell like a regular portable console, I doubt that Sony will limit the device to that.
Unfortunately it's pretty much set, they already demonstrated the device and revealed some of it's specs, it won't even allow for cloud streaming, really just PS5 within your home network.
Sony Reveals Project Q for the PS5, Alongside new Playstation Earbuds
Sony has showed off some new accessories for the Playstation 5 during the PlayStation Showcase event and the most interesting one goes under the internal development name of Project Q. The device is pretty much a dual sense wireless controller that has been split in half and each half has been...
www.techpowerup.com
Funnily enough, sony is licensing it's brand for smartphone controllers like this one and you don't need a particularly good smartphone to stream from your network/cloud (see the recent logitech g cloud, the thing is weak)
I think this project q handheld is really destined to be a massive flop, a 299$ price as microsoft is "predicting" (they probably know...) is crazy.