Lack of communication is Itch's main problem.
On the one hand, there isn't enough staff to respond and/or communicate with every person who requests support, much less to report issues like indexing.
Regarding an automated system, as far as I can recall, the admin has never given any reasons, but many of us believe it's to prevent bad actors from taking advantage. For example, if the system notified you automatically, you could program a bot to look for patterns of what is indexed and what isn't.
I also want to clarify that this is an assumption as to why it isn't done; it doesn't mean I justify or criticize the process.