Self-absorption and selfishness at the expense of others is a “filter bubble” that seems popular these days. While you could probably construct an argument that this slang isn’t the best description, that’s no reason to stop using it as shorthand for “a subgroup of modern social culture whose values are locally aligned but contrast with those otherwise proximal to them, whether physically or culturally”. Being selfish does not imply that you are a member of a local ‘cult’ of selfishness, so a group-focused slang will be required if you seek to replace that usage of filter bubble.