But why does it benefit the manager at all? Asset retention, right?
Indeed.
...
So is pursuit of asset retention all that different from pursuit of clients' objectives?

In a word, yes.
The best route to asset retention is failing conventionally and not
trying to outperform at all, or even try to manage the money prudently.
In 1999, asset retention and not getting fired meant buying .com stocks,
and that was diametrically opposed to clients' objectives of doing well.
It was in keeping with their short term emotions and myopia, which is a different thing.

Yes, I'm certainly being too harsh. Take me with the usual grain of salt, or more.

Mr Tilson firmly believes that the stock is worth around $180000/share,
and has made this opinion well known. He has backed this up admirably.
Given that the price was in the $120k-130k region for a long time, one
might assume that there as as big a margin of safety as one might
reasonably wish for and he would have built as big an allocation as was
warranted prior to the price jump—if he were good at his job.

I just don't see reasons that are good for clients in increasing the
allocation when the price rises and the value estimate doesn't.
That's simply buying more of something when it gets more expensive.
Wouldn't that normally be a time to reduce allocation, if anything?

Jim