The Realms question
Realms is the one place the mod's honest answer is "not much". Mojang runs the server, requires signing, and scans the chat automatically.
When the first wave of global bans hit, the pattern was hard to miss: nearly every banned player had been on Realms, and by their own accounts nobody was likely to have reported them. Mojang's own "Our Commitment to Player Safety" article explains why — for Realms they run "an automated proactive chat filtering system" to "classify, filter, and escalate online harms". In practice: every Realms chat is monitored, and a ban doesn't need a reporter. People have been suspended for swearing on their own private Realm.
That's why the mod shows Realms its own status: the red eye. Signatures can't be stripped there — the server is Mojang's, it enforces signing, and it logs messages regardless. Enforcement also demonstrably ignores context and consent between the people chatting, which is exactly the scenario players feared when reporting was announced.
If you must stay on Realms, the practical protection is moving the conversation out of Minecraft chat: encrypted voice mods, Discord, or the other channels collected in the encryption page's alternatives. The better fix, in Aizistral's words, is leaving Realms for a conventional host where the server is actually yours — he personally suggests BisectHosting (promo code AIZISTRAL, 25% off the first month).
Condensed from the official wiki's The Realms Question article, which stays the canonical reference.
For everywhere that isn't Realms.