Are there any diffusion models for text? I'd imagine they'd be very fast, if the whole result can be processed simultaneously, instead of outputting a linear series of tokens that each depend on the last
Diffusion for text is a nascent field. There are a few pretrained models. Here's one[1], AFAIK it's currently the largest open weights text diffusion model.
[1]: https://ml-gsai.github.io/LLaDA-demo/