Not true in all cases. Due to how the web security model works, unlike a native app, a web app running on wefwef.app cannot randomly access other domains. This includes contacting lemmy instances. This is the reason why they implement a proxy (see code here). From what I understand newer lemmy server versions do (or will soon) implement CORS which is a mechanism that obsoletes the requirement for a proxy and allows direct communication between web app and instance.
As they have not been mentioned before: We played „The Witness” and “Return of the Obra Dinn” together and are currently solving “The Case of the Golden Idol”