Byron called England a ‘tight little island’, by which I have always thought he meant narrow minded or socially restrictive. At the least given his life and sorrows that would be an acceptable reading. Of course he might have meant it was not cross-fertilized enough with other countries.
Shelley talked about the need for atheism so the two men when talking obviously saw religion was a narrowing of the intellectual arteries, something many have come to believe in the present day. It seems obvious that to believe a set of principles closes your mind to all others, but it is still the belief of many that the world is ‘just so’. Not just the world, the entire universe.
Wordsworth, when he was younger, definitely danced with revolution and liberation not just as thoughts, but as ways of life. But he had to fight harder for money than either Shelley or Byron and that fight cost him his zeal.
But given the chance all the Romantics would have fought for liberation of the individual to be artists. The greatest revolution there is, will never be political but always personal.