In my view it is (potentially) harmful, though it is not fair to judge
prematurely this particular effort.
Why harmful? It dilutes the effort to make the underlying program
better when "new" but essentially duplicate features are added,
and people who might be doing something more useful,
instead spend time debugging front ends, which ultimately
don't represent much progress.
I would rather see Maxima become more powerful as a math engine
than see it used as a kind of punching bag for every one with a
half-finished front end.
On the other hand, I am not immune from this hacking the front-end
tendency myself.
I can produce what amounts to a talking Maxima.
(mysp '(/ (pm (- b) (^ (- (^ b 2) 4ac) 1/2)) 2a)) -->
"<p>minus <spell>b</spell> plus or minus square root of <spell>b</spell>
squared minus <spell>4ac</spell> divided by <pitch
middle=\"2\"><spell>2a</spell> </pitch></p>"
under suitable circumstances, that string can be spoken aloud.
Under more carefully controlled circumstances, I think we can have
Maxima listen to the user and/or read handwritten math.
Whether this is progress or not, remains to be seen. :)
RJF