Two things:
1. I am mostly talking about handheld platforms. Grand Theft Auto 5 never has been released on a handheld platform.
2. Honestly that kind of logic might be bad for the industry and gamers. There are a few GTA level franchises and plenty of flops. Nowadays console games are huge risks with huge losses if you don't hit it big like GTA. It has led to an industry of cookie cutters and safe plays, and the destruction of whole genres that only have a smaller (though dedicated) fan base like JRPGs. Meanwhile handheld platforms have way lower development cost across the board, which has lead to innovation on mobile and the 3DS.
Actually mobile devices have twice the game consumer spending as all portable consoles combined since 2013:
I know that is the case for myself.
I could list off the long list of mobile games I like, or mention how I often use my tablet and phone with a six axis. But the truth is mobile devices have been a bigger platform for three years. Mobile is a way bigger market and developers notice that. Also Android is one of the best emulation platforms out there (second to x86 Windows IMHO) and many classic console games from companies like Sega and Squaresoft are already in both the iOS and Android markets.
Anecdotal data. The facts are if you compare that first chart with the one from this year:
You can see the numbers show the gap is growing. If any developers are going back to portable consoles its because they are quickly becoming a niche market.