What a load of crap. They must have done this poll in rural villages in North Wales to get a pro independence support of >20%. Theh know full well how dependent they are on the uk subsidies to stay afloat. Even to get from North Wales to Cardiff by rail or motorway requires you to go into England and changing at Crewe before going back into Wales. For someone who says Brexit will be a disaster for xyz reasons, you can capitalise them to XYZ reasons when it comes to leaving the UK, with the added fact that unlike the UK and the EU, the non English parts of the UK are heavily subsidised by London. The only part of the UK for which it would even begin to make sense to leave the UK is Northern Ireland because they are not as dependent on economic links with GB as the others are, but even then that would be frought with problems due to the fact the Republic would have to break it’s back economically to match public spending on the province, and they know it.
Dunno - but Plaid Cymru think it to be real enough for them to make noise about.
Remember - like Brexit - Welsh independence will be driven by the emotional need for Wales to be free of English domination.