Realistically a CEO isn't going to have time for more so you have to ask yourself would you rather have this or nothing. How many other CEOs even engage at this level?
The man has a company to run and some personal stuff to deal with. Yes I wish we got more detail but I'd rather this than nothing.
What you say makes sense, except when this substitutes for official communication from the company, as often is the case with Apple. If the CEO is aware of this issue, and the company prefers to keep mum on this topic, then it is obviously a considered silence.
Apple haven't replied yet. That doesn't mean that they're not going to reply.
Generally companies are ill advised to make knee jerk reactions to these situations. More customers and potential customers are joining the debate each day and if Apple made a statement today, it could be wrong tomorrow. This whole thing is less than a week old.
If Apple haven't responded in a month then I'd agree, however right now I think this is a sensible pause for reflection.
I think it's worse than nothing. Before there was one Apple position (the app store agreement), now there are two Apple positions (with the email). But can you really point to this email as justification for anything if your app gets rejected?
The man has a company to run and some personal stuff to deal with. Yes I wish we got more detail but I'd rather this than nothing.