Ok, the boxes might be smaller and slimmer, but they're still usually cone/dome drivers in boxes.
The age old problem is that in order to sell in viable numbers they will have to be domestically acceptable.
Given that maybe we could say that development has been rather constrained by circumstances rather than stagnating by lack of effort or will?
Perhaps the only real significant development has been the emergence of active designsalong with the increasing integration of subwoofers.
These days virtually every single professional audio monitor has its own built-in amplifier.
The main differences cited are usually accuracy (by far in favour of pro designs!) and the prevalence of near field designs in the professional world.
Perhaps there is some convergence between these two approaches, as there should be with the use of sophisticated measurements available nowadays, but few professionals would consider using a domestic loudspeaker for their work.
[Not even the truly iconoclastic Quad ESL].
The reverse might be said for many audiophiles, but that situation might change with the emergence of more measurement based sites like ASR.
Perhaps as a direct consequence we might see more consumers gravitating towards pro designs in future?
Nevertheless such sites still favour cone and dome drivers in boxes.
So perhaps those early loudspeaker pioneers were on the right track after all?