Do dall-e2 and stable diffusion models regularly get retrained? If so, as they get retrained using the ouputs of the models scraped from sites like this will w

Do dall-e2 and stable diffusion models regularly get retrained? If so, as they get retrained using the ouputs of the models scraped from sites like this will we see some sort of mode collapse? Is it reasonable for hobbyists to retrain these models with reduced or custom image sets or would that require a lot of money in compute?