I see the strum patterns as a phrase patterns or motifs (as in yamaha motif).
You can already arpeggiate a chord with strum patterns. It’s just a matter of retriggering the chord.
Sure it’s no arpeggiator, but I have quite a few devices that can arpeggiate here (besides my fingers which are pretty rusty these days) that I don’t feel the need for another one… but different artists different needs…
Cheers,
/R