Confusion about Saga pattern
Roman Liutikov

Agree for the Saga confusion. Even in the backend it seems to be used for meanings different than the original as you mentioned (the same can be observed for FRP: discrete event streams vs FRP as specified by its original author Conal Elliott, yet no one — except the author — seems to complain on this). As for the origin of the name redux-saga you can consult this discussion :

Do not agree actually on CSP. While v0.10 actually introduces channels in redux-saga their semantics are different from CSP channels. In CSP puts are synchronous (blocking) while in redux-saga are not (much like in the actor model). Also buffering is different in the 2 models: in CSP buffering is used to unblock the sender while in redux-saga buffering is a simple mechanism for message queueing.

CSP is a more fundamental model of computation (like turing machines, DFAs, Actor model …) which defines a formal algebra for concurrent systems What defines CSP is not the API exposed (take, put: there is no take/put in the formal model) but rather its formal semantics