Remote play is not some secret mystery, it's existed for close to 2 decades and millions of people use it. There's no need for both ends to have "VERY" good wifi, just decent wifi will suffice if you're outside your home and there are plenty of people who do that. You can use a hot spot on your cell phone as well. The requirements for remote play are 15mbs download and 5mbs upload minimum / 30mbs download and 10mbs upload recommended.
This is a device with the specific purpose of streaming games and it's designed to do it very well with fewer compromises than using a phone or tablet to do remote play. Sony knows how many people use remote play and what sort of devices they use them on. They've had nearly 2 decades worth of data behind this feature and that data was sufficient for them to greenlight a dedicated handheld device.
Now it's easily possible that the functionality of this device will be further expanded if or when Sony develops an Android cloud streaming app. Even without it, there's a large enough pool of remote play users to cater to, and an even larger potential audience who might want to jump into remote play via this device. It's meant to be the, "it just works" poster child of remote play.
Here's a link to the fan-FAQ I created for the Portal. It should help answer some of your questions
If the last few days has taught me anything, it's that a lot of folks don't know who the PlayStation Portal device is aimed at, and there's a fair amount of confusion over how it can be used. While we await an official FAQ from Sony, I thought it might be nice to help clear up some things for...
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