For quite some time, we hadnt seen SEGA do much with Sonic as he was known during the Genesis days. But the character was represented in Sonic Generations before starring in Sonic Mania, which featured remixed zones as well as a few brand new ones. Thankfully, classic Sonic is still being considered for SEGAs future.
Source: N4G PC Sonic boss: classic Sonic "will hopefully be a part of the blue blur's future"