Like I said,

Away from the south and the more touristy areas, you’re likely to find people speaking Welsh in everyday life (education, shopping, workplace), rather than just at home.

If the furthest north you went was Methryr Tydfil, you were never more than 15-20 miles from the M4 corridor, which is where the most strongly English speaking areas are, (apart from South Pembrokeshire and some more touristy bits).

I’m not surprised that you found mostly English speaking in the mostly English speaking parts of Wales. If you had stayed in East Anglia you might have concluded that England possessed no hills at all, but it might be worth admitting that there’s more to know than that.

So,

I just said that you could grow up in Wales never learning Welsh,

(apart from it being compulsory in Welsh schools)

because English is just as much (if not more) the language used in every-day dealings

in the South and more touristy areas, whereas Welsh is the main spoken language in much of the country further North.