I dont understand what u mean here.
It's a little joke from the time the Sons of Glendower were torching English holiday cottages. There was an advert on TV at th time for coal central heating "Come home to a real fire". The "Not the 9 O'clock News" team (Rowan Atkinson, Mel Smith et al) did a parody... "Come home to a real fire... buy a cottage in Wales".
I understand what you mean about the mines closing etc. My mothers side of the family are from Tyneside and my aunt was living in a mining village during and after the miners' strike. It wasn't just the Welsh Valleys which suffered. I grew up in Shropshire. The area around thre used to be full of mines. None now tho'.
I admire Welsh cultural patriotism. What does bug me is when it is just used as an excuse for anti-Englishness rather than promoting the positive aspects of Wales and welshness (same with any patriotism, really).