There was some time when PokeStops were only giving out two items at a time. But this was sneakily fixed, which left us, players, wondering if this was only a glitch.
These past days, the developers of the game completely changed which items can we get from PokeStops. While they still give us PokeBalls and berries, they do not release potions or revives.
Side note: Not entirely dropped, but extremely rare. But, potions and revives can still be obtained from gyms, together with PokeBalls or berries.
Some players stated that right now, gyms give more potions and revives than usual, though this is not tested yet.
This new change has not been announced by Niantic yet, there is a ton of evidence that is showing this decision.
This new change is not a positive for all though. There are two types of Pokemon players: the ones who are competitive and need potions and revives for their Pokemon to remain healthy, and the ones that only want to catch Pokemon, which do not need potions and revives. If some players rely on gyms to get their PokeBalls, they might not be content with getting more potions and revives instead.