Racing games, once you are good at them, fit this bill. I can win online races while watching YouTube videos in Forza Horizon.
But I’d say Farming Simulator is my favorite game to play while listening to podcasts or watching YouTube videos on the side. It’s got enough going on to keep you engaged but you aren’t doing any actions that are time critical or require deep focus.
I feel like if you tried to train an LLM on spoken conversational English the output would just be “yeah um yeah um yeah um”
But on a more serious note spoken English is very different than written.
Either way you can find validated sources of human written text it just won’t be as easy.