is a misleading term. Perhaps, due to widespread Western European imperialism and missions, Latin (ie, Western Rite) Catholicism and Protestantism qualify, or Christianity as a whole (especially since adding-in Orthodoxy, Eastern Catholicism, the Oriental Churches, and the Assyrian Church, adds-in Eastern Europe, Asiatic Russia, half of Kazakhstan, half of Lebanon, Armenia, Georgia in the Caucasus, Ethiopia, Eritrea, and Kerala state in India – together a large part of the “world”).
Anything else has spread relatively little beyond its home ‘zone,’ with comparatively little emigration and evangelization. Islam certainly straddles the globe, from Morocco to Indonesia, but outside that region is not so well represented. The religions at home in India are still overwhelmingly there and vicinity; elsewhere by comparatively little emigration and conversion. Buddhism: East Asia. Judaism is certainly well-scattered, but due to conversion, persecution/genocide, and lapse, is so small in numbers… though its influence far outstrips its numbers….
Which brings up the matter of influence beyond actual adherents. Certainly Buddhism and Hinduism have had unexpected influence on “Westerners” in the last couple centuries, in part on account of the British Empire, and also Liberal Protestantism’s opening-up to “dialogue” with “Eastern religions,” as well as celebrity conversions and explorations in them. “New Age,” Neopaganism, and the rising profile of the world’s Indigenous peoples, for that matter, have revived or magnified the influence of numerous old and new esoteric and other kinds of faith-practices, philosophies, and concepts among Westerners, aided by seemingly-rampant religious illiteracy in the West(!).
So maybe instead of the term “world religions,” we should talk more clearly, on the one hand, of the largest religions, and on another hand, of influential religions.
Or am I seeing it as a Westerner, and overestimating “influence,” say, deep in India or Africa or China or Japan?! 😉