BehaviorSubject Is a Loaded Gun

It holds state, pushes values, and is hot by default. That means:

— Every new subscriber instantly gets the last value
— You must manually manage .next() calls
— It often leads to imperative logic (e.g. if (...) this._value$.next(...))
— And worst of all?

It gives you a stream, but not semantics.

You can’t know if the value is:

— Cached
— Live from server
— Derived from another value
— Meant to be read-only