The first problem with this argument is that referential transparency is a property of syntactic positions, not of languages.
The second is that languages like Lisp, SML, C, Pascal and BASIC all have referentially transparent and referentially opaque positions in exactly the same way that languages like Haskell do.
This means that all these languages enjoy referential transparency in the same way, because when you unpack the notion of equivalence, referential transparency itself is within a whisker of being a tautology: if a is equivalent to b, then you can substitute a for b or b for a. The relevant sense for "is equivalent to" can really only be contextual equivalence, which is all about meaning-preserving substitutability.
That said, not having to reason about effects within one's program equivalence sure makes things simpler in a pedagogical setting. But that's not to do with referential transparency per se.
The second is that languages like Lisp, SML, C, Pascal and BASIC all have referentially transparent and referentially opaque positions in exactly the same way that languages like Haskell do.
This means that all these languages enjoy referential transparency in the same way, because when you unpack the notion of equivalence, referential transparency itself is within a whisker of being a tautology: if a is equivalent to b, then you can substitute a for b or b for a. The relevant sense for "is equivalent to" can really only be contextual equivalence, which is all about meaning-preserving substitutability.
That said, not having to reason about effects within one's program equivalence sure makes things simpler in a pedagogical setting. But that's not to do with referential transparency per se.