I think the bar is being set too high for "fresh ideas" here. TikTok perfected a totally new social media form factor and they only caught on in the last couple of years.
BeReal got huge and that only got huge in the pandemic.
There are only so many ways to transmit information, if you don't count TikTok text posts or Threads as innovative because they are written text like Twitter then maybe there will never be innovative social media again, it's all gonna be text, video, or still images.