Over the past decade or so, Blender has been on par, and even ahead of "industry standard" tools.
It isn't required to split its focus. It is able to. That is something proprietary software from a company would fail at. It's something that free software and collaboration succeed at.
The biggest benefit is that it has all of these tools in a cohesive environment.
Instead of a photoshop/GIMP-like menu of functions, Blender is a cohesive manageable UI.
There are, in fact, a wide variety of professionals using Blender to make money. You don't hear about it, because telling you what they use is not their perogative.
What features to Maya/Max/etc. have that Blender is really behind on today? I can't think of any.
Now, there is at least Neutron as an open source compositing tool that seems to be filling that particular hole now much more competently than Blender ever could.
I do not understand how you can consider Blender's UI "manageable" in any way. There are much better ways to build UIs for enormously complex DCC tools. My go-to example for that has been Maya for a long time, but since a couple of years, Autodesk has bolted on features in a way that spectacularly breaks the internal consistency, logic and general discoverability of features in Maya. Even though, Blender's UI is still an unsorted mess compared to that.
Expanding feature sets is something commercial software fails at? The biggest reason nobody professionally uses the open-source alternatives is they're missing features.
Blender is striving to meet the features and capabilities of Maya and 3ds Studio, not the other way around.
A more "business" orientated sentence:
Blender is required to to split its focus to provide a complete movie/game making package including a movie editor, shader editor (i.e. photoshop), and animation editor, an audio editor, a physics editor, a compositing editor, and a game editor; Maya and 3ds Studio do not.
Blender just can't keep up. It's a good tool, no doubt about it, but few professional users will end up using it to make money.