Indeed 5 months isn't that bad.
It's rare enough to have games provide regular content updates. Knowing that it will come after X weeks/months is fine by me.
Better than having to be in constant hope that something will happen eventually in the near future.
IMO the issue is not the release calendar, it's the fact that most content is short-lived.
And I think they are well aware of it, and having 2 PvP seasons per patch is a step in the right direction to fill the gap. (as long as the rewards for the seasons are worth it in the future)