Timing decided what each place inherited
This is the single most useful idea for understanding Asian tea culture. Japan received whisked powdered tea, associated with Buddhist monastic transmission around the Song period, and kept it — which is why matcha and chanoyu exist there and largely stopped existing in China. Countries that received tea later received loose-leaf steeping instead. A tradition’s shape is largely a fossil of the Chinese practice current when it arrived.
Japan and Korea
Both have long-documented associations between tea and Buddhist temple practice, and in both cases the transmission ran through monastic contact with China. Japan developed chanoyu around whisked tea and later senchadō around steeped leaf; Korea developed darye, with its own vessels and pacing. Korean practice is consistently under-described in English-language accounts, which reflects publishing patterns rather than significance.
Overland to the north and west
Compressed tea travelled overland into Tibet, Mongolia and Central Asia along established exchange routes, and the teas made for those markets were designed for the journey: coarse, mature, heavily compressed and intended to be boiled rather than steeped. Butter tea, salted milk tea and brick-tea preparations are what that trade produced at the receiving end, and they are staple foods rather than beverages in the Western sense.
South and South-East Asia
Tea reached parts of South-East Asia through both Chinese migration and overland contact, and indigenous large-leaf tea occurs across upper Myanmar, northern Thailand, Laos and Vietnam — where it is eaten as well as drunk, in fermented-leaf preparations such as Burmese laphet. India is a different case: while wild tea existed in Assam, large-scale Indian tea culture is a nineteenth-century colonial construction rather than an ancient inheritance, and chai as it is now known is more recent still.