Today’s r/bitcoin freely allows the discussion of hard forks to the protocol. I see threads and posts all the time promoting BIP103, BIP100, and other changes to Bitcoin.
Bitcoin XT, at the time it was moderated away, was being “sold” as something that miners could force the rest of the network to accept, by merely mining it.
Rather than go through a BIP process, and do the research and prove that nodes could handle the traffic, and come up with metrics like the number of mbits a node would need and how large the chain would be in 2 years and how fees and network resiliance would be impacted… the XT group chose to endorse “attacking the primary chain with hashpower”.
That is an Altcoin. And it’s a particularly damaging one at that. And willfully promoting alt-coins and hack attacks on the network — should be moderated away. Bitcoin Unlimited is a similar proposal.
BIP100, on the other hand… which has a similarly ludicrous and aggressive growth rate of allowing the block size to *triple every year* — is freely allowed for discusson on r/bitcoin.
Why? Because it was proposed as a normal protocol improvement. And sure it may never achieve anything resembling consensus. But nobody is trying to force it upon users without going through a normal development cycle.