For the past decade that's been the name of the game. Companies worldwide have been doing EVERYTHING they can to cash in on people's nostalgia in any and all forms. Reboots, retreads, remasters, and so on. This is especially true in the world of video games, as there have been a lot of HD remasters lately. And let's not get started on the crapton of indie games that insist on emulating NES/Super NES fare in terms of look, sound and feel.
As early as 2010, Sonic has been guilty of this. Starting with Sonic 4, SEGA has been going out of their way to win back the elitists, hardcore retro players, and press, by pumping out as many callbacks as they can get away with. But while it was acceptable for the Modern Era to end that way, it became ridiculous from 2012 onward. Gamers don't care, though. As long as they feel like kids again, everything is fair game, even if it's at the cost of a franchise's integrity or evolution. On the other side of the coin is what can happen if you try to give a franchise a side universe for a new audience...and have the first attempts be well intended misfires that damage the wider brand.
This era was certainly the most uneven the Sonic franchise had been through yet. Something drastic needed to happen to shake things up, and fast...