Yes, this what the people who will curse you out and judge you for not using wide events omits: it will greatly increase storage costs compared to the normal metrics + traces + sample based logging that is conventional. It has both a benefit and a cost, and the cost part is always omitted.
Properly implemented wide events usually reduce storage costs comparing to typical chaotic logging of everything. It is expected that a single external request leads to exactly one wide event with all the information about this request, which may be needed for further debugging and analytics. See https://jeremymorrell.dev/blog/a-practitioners-guide-to-wide... .
How would you add an outgoing request you make to external system in the wide event?
For example, I receive a request, in that request I make a HTTP call to http://example.com. In tracing that will be a separate span, but how you manage that in a single wide event?
