This is also true in the US. People pick up enough written English to get by most of the time, but it's often quite broken and clearly a second language. I know hearing impaired people native to the US with substantially worse English than the average European.

Just so you know, "hearing-impaired" implies that a person has a flaw whether a person is born with it (it is natural to them) or impacted in later life (hearing-challenged).

Most non-offensive way to refer to a group of people without perfect hearing is "hard-of-hearing or deaf".