I do agree that employing arrests as a tactic is exclusive (although here people aren't left to themselves to cover legal fees), but it must also be said that this that XR has a wide range of roles and types actions to participate in that do not involve getting arrested.

Those first two paragraphs strongly depend on the location, in particular the situation wrt. police. Many countries (certainly mine, the Netherlands) do respect the right to protest and employ the police to facilitate and protect these rather than to 'put down all protests'.

When activists seek the limits of these protections, e.g. with blockades, I think it's right that they seek to find the way to be most effective, which can involve negotiating with authorities or choosing not to pick certian battles. Case in point, Amsterdam has employed 'bestuurlijke verplaatsing' (stuffing people in to buses rather than arresting), which is legally iffy but it's a) less work for authorities and b) much better than getting properly arrested. A status quo that allows more inclusive mass actions.