In the Creator Dashboard create a setting that allows the incoming Raid chat accouchement to be Broadcaster/Mod View only, or auto replaced by a /Shoutout prompt.

If you are a Broadcaster, who has no Raid limits set (because that choice is anti-Discoverability for a growing channel) then there should be other safeguard options in place to help with 1-10 viewer Raids which may entirely be coming from Offline channels.

So, to help with excessive chat spam and keep chat focused on it own conversation flow, there should be an option to mark Twitch genenerated chat messages as Broadcaster/Mod view only. Goal = Cleanup & streamline normal viewer chat