If you were fully updated to the latest iOS last October and got infected, it would keep you infected. They also said they found the malware has been deployed in the wild since at least 2019 and this is the first discovery o. f it. And it appears to be a fully remote, stealth infection against all iPhones.
I'm no expert on security (or iOS) but it sounds pretty much like worst case to me.
Only the top of the iceberg is being visible to public if not less.
To be precise there is one "Messaging" app, that automagically uses iMessage (blue bubbles) instead of SMS (green bubbles) whenever possible. One can turn off iMessage in the settings, which will probably lead to your iPhone rejecting iMessages, making other iPhones only send SMS to you and also make your iPhone only send SMS. Whether that toggle prevents receiving and processing of malicious, invisible iMessages is an entirely different question.
To sum it up to have it as fancy as possible to users it checks various things and needs permissions for that. Enough 0days in the chain and you can do whatever you need.
This is the problem of closed systems, you have to trust manufacturer 100%, there is no independent audit possible. And if you ever did any serious code before, you know by heart that any code has bugs, in the code, in platform/VM it runs, apis etc.