How it differs from chanoyu
A description of something people do now, compiled from published accounts rather than from practice.
The tea is steeped leaf — sencha and gyokuro — rather than whisked powder, the utensils are different, and the aesthetic reference points differ. Very small pots and cups are used, and the pouring sequence distributes strength evenly between guests in a way comparable to Chinese practice. It is a separate tradition rather than a variant of the tea ceremony.
Why it is less visible abroad
TeaHQ's own reading of well-attested general knowledge, with no single source behind it.
Chanoyu travelled with matcha and with a great deal of outside writing; senchadō did neither to the same degree. Visitors to Japan are far more likely to encounter a chanoyu demonstration, and a good deal of English-language writing presents chanoyu as though it were the whole of Japanese tea practice.