I've never seen an ad on Discord, but I have seen them trying to sell premium features. When I talk about Discord being "anti-gloss", I mean all live-chat formats, Discord, Matrix, IRC, etc.
Using matrix.org to post in public/private chat rooms is practical, and can chose any client to CRUD content, or subscribe to rooms (feeds). Element allows export of room contents (with attachments) to JSON or XML. https://libli.org/libli-news:matrix.org