Good inbox/read relays enable their users to shield themselves from association with spam and vulgar replies. No one is censored, as those types of replies can be made at many other locations, and anyone can access those locations to read them if they want. WoT, mutes, and reports can be an active defense for the individual while user-respecting inbox relays can passively enhance the reader experience for all parties. Neither approach is perfect alone. A more-perfect client would enable any user to choose from which source they are choosing to read replies, while also equipping them with the tools to clean up their own experience when necessary.
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