Midjourney is an interesting case study in this I think, building their product UI as a discord bot. It was interesting to be sure, but I always felt like I was fighting the "interface" to get things done. It certainly wasn't all bad, and I think if I used it more it might even be great, but as someone who doesn't use Discord other than that and only rarely generated images, I had to read the docs every time I wanted to generate an image, which is a ridiculous amount of friction.