Working at a large company, I was once informed that the company logo should, on a dynamic user interface, do exactly nothing. Clicking on it was not to go home or help. Much as I disagreed, the powers that be dictated otherwise.
Could be similar reasoning here: lawyers or marketing or some such got involved.
It is fine, if it refreshes the current context (in Gmail inbox, for example).
In Gmail, the search bar next to it searches Gmail by default, so that would be consistent and expected. There will be much resistance if that bar starts searching other things.
Could be similar reasoning here: lawyers or marketing or some such got involved.