Yes, Sonic Mania is the Sonic you remember
For its most recent venture back into the land of 2D Sonic games, Sega enlisted famous Sonic fangame developer Christian Whitehead to develop a new title evoking the exact spirit of the originals. The result, Sonic Mania, is just as much a return-to-form in person as the trailers have made it out to be.
Sonic the Hedgehog, as a franchise, is an interesting beast -- a professor friend of mine once remarked that the games actually aren't all that good to begin with, arguing that their swift pace makes them thrilling for young players and no one else. A great, great many adult game critics and journalists would dispute that assessment, but it's true that 3D Sonic games have largely failed to capture the speed and breadth of their 2D counterparts, and even Sonic 4 -- an alleged return to the 2D style, struck many as a disappointment.
Well, inasmuch as nostalgia counts for anything, Sonic Mania is indeed the Sonic game of your childhood. The input-to-action response time is the same. The jump height is the same. The enemies populating the Green Hill Zone reconstruction I played today on the E3 show floor behave just the way they were encoded into your muscle memory all those years ago. It is, pixel for pixel, classic Sonic.
The big difference in Sonic Mania's Green Hill Zone demo versus the original as the boss battle against Robotnik (I guess we're calling him Eggman now?), who in a bipedal mech will slowly corner Sonic, Tails, or Knuckles -- you can play any of them right from the get-go -- at the edge of a cliff with homing bombs and an extending drill arm. The usual Sonic boss battle technique of "jump on it until it stops moving" still applies here, but the bombs introduce an optional secondary strategy, if you're feeling clever. I died anyway, which to be fair is also how I remember Sonic games playing out when I was a youngster.
My brief hands-on at Sega's booth didn't offer a long enough look at Sonic Mania to really grasp how its levels and challenges evolve over time, so I can't say for sure whether the entire game -- which bills itself as part remix of the original levels, part all-new design -- will measure up to people's rose-tinted memories when it arrives this October. But I can say that from top to bottom, Sonic Mania looks, sounds, and most importantly feels the part in your hands, and I'm extremely here for that.