One drawback for suggesting as a workaround to visit the original website is if it would incur a huge cost, such as if the webpage and its assets took a lot of time and network bandwidth to load up and could track & fingerprint the user quite a bit.
In contrast, it would take orders of magnitudes less bandwidth if a webxdc integration had access to the precise data resource (either from a separate XML, JSON, RSS, Atom or protobuf file or parsed out from the shell HTML) without all the naggers.
Another possible advantage compared to visiting the webpage would be if automation was involved, such as a (system-) webxdc that kept checking the given API endpoint (or HTML) for changes according to a schedule so the user would not have to and notified the user of events immediately (e.g., by notification or by synthesizing a new message from such an event).
If the target scenario involved on-demand fetching and aggregating information from multiple sites (even if it’s just a few or up to a dozen), it would still be vastly superior if it could be automated than if the user was forced to tediously open each bookmark and visually connect the dots.
One distinct disadvantage of suggesting to proxy such traffic through a central bot (other than affordability) is that certain service API will then start blocking you due to the volume and pattern of traffic coming through that single IP as multiple users are sharing the same bot.
Chat apps in the 90s and 00s had plugins/scripts similar to webxdc and quite a lot made use of network access. I can’t find a good overview of this, but you could find features such as
- sending a rich preview along with your link (from basically any site you have already visited after confirmation)
- following feeds,
- weather forecasts,
- search content on various portals (the web, package managers, multimedia memes, Wikipedia, book, movie & music metadata),
- compute with Wolfram Alpha,
- integrate with VCS & ticketing,
- link shortening, snippet creation,
- meeting & eventing,
- monitoring your sites for uptime,
- evaluate code snippets in various languages in a VM sandbox
- start an interactive telnet session to a BBS (this is actually seeing a resurgence now)!