To the general public sure but not research which is what produces the models.
The idea that diminishing returns has hit because there hasn't been a new SOTA model in 9 months is ridiculous. Models take months just to train. Open AI sat on 4 for over half a year after training was done just red-teaming it.
Keep in mind GPT-3.5 is not an overnight craze. It takes months before normal people even know what it is.