Armageddon definitely does not have much OOC communication and collaboration. That's by design. But that isn't to say there's no IC forgiveness for OOC mistakes, either.
The instance of new players not knowing their character is illiterate is often raised as an example of Armageddon being unforgiving. In many years as a player and staff member I can never recall someone actually experiencing permanent consequences for a slip of the tongue with regard to literacy. Usually a combination of IC prompting ("What do you mean, read? You mean heard? No commoners can read of course, that's silly.") and light use of OOC ("Hey, see 'help literacy', your PC would know that reading is illegal) happens and the new player is corrected, and everyone forgives and forgets. In the moment, yes, there might be some IC consequences (someone questioning you), but an IC reply of ("Oh right, sorry, I misspoke") is almost always pretty much the end of it. For all intents and purposes the "retcon" happens, it's just not OOCly explicitly stated as such. I understand that it would feel frustrating to make a mistake your character would not make, but other players understand how that feels too and do not go out of their way to haze you over it. I can say definitively that if the staff felt like the opposite was happening, we would step in.
This usually goes down in the same way for other mistakes like not bowing to a templar, running around the city with your sword drawn, and so on.
In a MUSH or MUX or even other RP MUDs, these same sort of corrections probably happen more often via OOC channels. Armageddon and the RPI genre tends to downplay use of OOC. There are advantages to having more OOC and advantages to not having it; but anyway Armageddon doesn't. My point here is that that corrections of OOC mistakes still happen in Armageddon even if usage of OOC chats aren't as prevalent.
But definitely, there is no denying that OOC communication looks different on Armageddon vs. other MUSHes. There is no discussing a scene in advance or during or after via OOC with other parties involved. There is know "would my character know..." sorts of discussion that happens via a sidebar. Everything you know about the other characters around you is intended to be discovered purely in character via in character means.
These are design decisions that are probably going to feel different to MUSH players, and yes, they may make the game feel less welcoming, unfortunately. All I can say is the player and staff community is as OOCly welcoming to new players, and especially recently with the Discord channel I feel there are great opportunities to OOCly connect to the community and get help.