More importantly, it is a built in way to show lots of generated content to a large audience, which can then thumbs-up content they like, which gets fed back into the model that X result was better than Y result.
Probably. If your small team is competent at ML model development, why spend time building a web app?
One time I participated in a small local event that required submitting photos via tagged Instagram posts. I was annoyed at that, until I realized it completely eliminated the need for any technical expertise for the organizers.