Planning as in corporate communities have little concern for the green-centric, free lifestyle, and emphasize materialism of thought and lifestyle.
Seeing "corporate" planning in Spock's tirade is but one way to interpret it. But planning is key to being green, and it is impossible to be green without planning at a communal level. Free lifestyle can never be ecological.
This is a more current "surprising accuracy" about the tired old dialogue than its "prophetical" 1960s-70s interpretation.
Those professing a green lifestyle reject the pre-fab, materialism/clone mentality seen in such communities
Sure. But planned communities (not "such", but of other sort, which Spock may equally well be interpreted as having referred to) are the only way to a green lifestyle. Rejecting the artificial and the manufactured categorically, without thought, only leads to excesses and unsustainable exploitation of resources. So perhaps we should hear in Spock's words a deep damnation of Sevrin's ideals, equally abhorrent to our fellow Vulcan as the idea of the little caveman still living inside all of us.
In the very next phrase, Spock does deny he feels any sympathy towards the group... And has difficulty understanding their way of thinking, perhaps because it makes so little sense, to him and to the 21st century audience.