Not at all, if you fork Discourse your posts get flagged as #unsupported-install.
If you use a third party package, or fork Discourse, you receive zero support. Paid customers have a dedicated support channel, best-effort support is provided with the above requirement, there aren’t any exceptions here. The volume of users you see are all on a supportable track.
You’re asking to modify a feature which is still in-development. Ignoring users has only been possible for around 17 days as of 2.3.0 beta 7. As @pfaffman mentioned above you might be able to achieve this with a plugin, although as we’ve already indicated there are workarounds.
As we’ve already ascertained, TL2 is quite easy to achieve. If this is a dealbreaker for you then it’s time to learn to write a plugin or take it to the #marketplace.