Perhaps my experiences in England and Ireland were not exemplary of the norm. How could I know, given the brief time I was there? But my sense was and is that virtually anyone with a voice loud enough to be heard above the usual din of a pub, could raise a song and feel somewhat certain that at least a few others would be likely to join on the chorus. I won't say this could occur in every pub in the nation, but I would daresay it might be true in many. In contrast, an attempt of that sort in the USA would almost certainly fall flat. In general, people here don't know and don't care about the old songs. Praise be to the gods that there are some who still do!

Now, I know I made a blanket statement regarding the old songs. I know full and well that there are places one can find if one searches diligently where folk music in its various forms can be heard in the US. But my sense is that such places are not nearly as ubiquitous as they are in the UK.