If you allow user-generated content in your app, you eventually run into a massive liability problem. Users will upload NSFW images. I ran into this exact problem when Apple rejected my previous app under Guideline 1.
Source: [Dev.to](https://dev.to/tabushield/how-i-built-an-in-memory-explicit-content-filter-in-nodejs-200ms-latency-zero-images-saved-jl4)