The program is a music theory tool. it would be a good feature if it were possible to write notes such as rhythm or melody on the score line. Of course, not everyone would be able to take advantage of it, but for some it could be of great benefit.
I think notation programs are much better equipped for such an endeavor. The idea of Scaler is quickly making music and learning. It would add too much to a program that few people would need.
I agree with @jamieh
It is inevitable that in complex processes such as music creation, there are generally a series of serial operations (and applications), and it often hard to decide where certain functions should live, or whether tthey should be duplicated.
IMHO Scaler’s sweet spot is well defined and (as an entirely personal view) it should not aspire to compete with the primary DAWs or specialist applications like notation. There is a good reason why Ableton don’t so this, but of course many others will see it differently.