Consider the platforms; they toil not (but spin do), according to Brent Sheather in his first letter to the custodians.
I sympathise somewhat with his viewpoint. In my (too) long career writing about platforms - a broad term covering a number of different technological and legal structures - I've often come to the conclusion that they're nothing more than software-enabled ticket-clipping machines.
Sheather is right, too, that investment platforms tend to be constructed with the adviser in mind first; are prone to product bias, and; lend themselves to all sorts of back-room deals (such as the infamous 'shelf space' fees).
He forgot to mention, as well, that platforms can have tricky tax consequences - getting out, like many things, can be easier than getting in.
Nonetheless, Sheather's is wrong to state that platforms are not "necessary in any way, shape or form". Or, at least, the idea of platforms, the ideal platform, is a valid one.