Maybe it’s a particular region where you are? Your town? Work place? You are in UK right?

I have close family in UK, London and I travel there several times a year. It’s not a prohibited topic at all. In fact a family member of mine has her share of mental health struggles and it’s nothing secretive or taboo. In fact people mostly understanding and discuss these topics

Of course it depends on where and how you are discussing mental health issues? Context is important