[inbetween]

That's technically wrong. Every language has morphemes for the simple reason that every word is at least one morpheme. `cat` is a morpheme. `cats` is two morphemes (cat-s).

(The point about semantics is also technically wrong. You would first need to specify your view of semantic compositionality before such a point can be evaluated, but the usual views of semantics don't have any such consequence.)

[darby_eight]

> Every language has morphemes for the simple reason that every word is at least one morpheme.

Sure, if you define "morpheme" as a collection of syllables that's meaningful to people using alphabetic script. I don't see any benefit to this compared to working with syllables directly, which is a meaningful concept regardless of the script used to encode them.

[dragonwriter]

> Sure, if you define “morpheme” as a collection of syllables

Cats, as noted, has two morphemes, despite having only one syllable. Syllables and morphemes are largely orthogonal, morphemes can be less than, equal to, or more than a syllable (and even when more than, may or may not start or end on a syllable boundary.)

(Also, syllables aren’t the minimal semantic units even of spoken speech, those are phonemes – a syllable consists of at least one phoneme, potentially more. But morphemes, even an alphabetic script if it isn’t perfectly phonetic, still don’t necessarily map to one or more phonemes, since is textual semantic unit may have no effect on pronunciation.)

[inbetween]

You might not see any benefit, but that's what those words mean :) Grab any textbook, it is linguistics 101!