Excellent point, Olygirl!

Dementia manifests itself in such a wide variety of ways, so generalizing can be problematic.. however, in my father's case he lost the ability to speak coherently long before he lost the ability to understand.

It was clear to family, friends, and most importantly care staff that he understood what was said to him, even when his responses were nonsensical. Knowing that he understood determined much about how he was cared for.

If he had been placed somewhere he did not understand the language, even with the most caring and attentive staff, that he retained cognitive function might not have been apparent. That last vestige of dignity would have been taken away from him.

Just something to think about, OP.