At its best phone gaming conists of people running DOS box on their phone and playing DOOM with a bunch bluetooth mouse, at its worst phone gaming is a bunch of shovel ware gache trash appealing to the lowest common denominator.
To put it bluntly, your whole comment shows you have zero clue about the mobile gaming market, how big it is, the overlap, and what people are actually playing.
The reason why phone gaming will never take over the computer/console market is because it is just absolutely filled with shit, also phone are just too underpowered and clunky when it comes to controls.
Absolutely not. There are a lot of naff games, as there are on consoles, but a shitload of games which have brought out hugely competitive scenes. The mobile gaming market has already taken over the handheld scene; yes, the Switch is popular, however people game on phones in far bigger numbers. League of Legends on Android alone has over 50m downloads (not sure the exact number), plus Apple downloads and it's more than any Switch game. There are multiple games with these numbers, and far from clunky.
"Underpowered" is a joke; we've had powerful gaming phones for a fair few years now, many are more powerful than a Switch yet they aren't good enough in your eyes? My phone (not a gaming one, just a Pixel) plays Dreamcast games better than my Dreamcast did, and whatever else I've thrown at it.