Description of the need
I suspect that most people who enable the core Contact form do so in order to allow visitors to contact them, without needing to provide their email address publicly. As such, I also believe that most emails recieved through the contact form have nothing to do with feedback about the website itself (that seems like a very specific use-case).
Proposed solution
I therefore propose renaming the default Contact form category from "Website feedback" to something like "Website enquiry", or just "Enquiry". To me this seems more generic and a better default option.
Alternatives that have been considered
Users can always just edit the default category themselves (I personally have to do that all the time).
Additional information

Recent comments
Thank you, this is a very useful workaround for preparing a clean import list. One concern remains, however: if Simplenews 1.x-1.2.3 still treats blocked user accounts as invalid...
Re-enable Simplenews newsletter subscriptions that had been erroneously disabled
@Amilenkov, I have an idea for your use case where you want to avoid re-subscribing people who have explicitly opted out: Build a view of simplenews subscriptions, and filter by Status (...
Re-enable Simplenews newsletter subscriptions that had been erroneously disabled
"modules to help someone monetise their own website"
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