

You don’t need to speak Latin to notice common roots and get a gist for what a term means.
If you’re actually in a position where it’s useful to distinguish one type of dementia from another, having a meaning that’s linked to what the symptoms are may help you remember both name and symptoms.
If you’re not a medical professional, remembering either name or symptoms for specific types of dementia is unlikely to be useful.
I was specifically addressing your line about Latin.
I’m not really clear on what the aim of your broader point really is actually driving at. If someone struggles with language acquisition or production, yes they may struggle with the complete name of their specific diagnosis.
If communicating the specific name to the outside world is important, having it written down somewhere may help. We use tools to help move our bodies. Why wouldn’t we use tools to help extend our brains.
If it’s truly important to have the specific name, the other party may need to look it up anyway, which is easier with a spelling.