Ghetsis is a Supporter; therefor when you use it, you are giving up a chance to use something more important, like N, Professor Juniper, or Skyla. By the time it comes out, we should also have access to Colress (while likely weak first turn of the game, even by the overall second turn it should at least function as Professor Oak's Research). The realistic draw yield of Ghetsis is probably two cards.
Something to remember is that Ghetsis isn't discarding those Items, but shuffling them back into your deck. "Burning" Items just to deny me one more card drawn per Item? Sometimes it will be a fair deal, other times it will flat out benefit one player over the other... but it can go either way. Burn Computer Search, Crushing Hammer, Enhanced Hammer, and a Pokémon Catcher all in one turn? That can really hurt ltae game.
Even things that might seem "safe", aren't; tossing down Random Receiver since "Hey, Ghetsis doesn't hit Supporters!" or using up Ball Trainers since Pokémon aren't clearly not affected by Ghetsis ignores that N is still present and likely still a force. In that way, the two sort of compliment each other. If your opponent burns up their Items, they are denying themselves an important resource even if an N grants them a good sized hand. This it the reason one doesn't needlessly burn deck thinning cards right now.
Ghetsis is also odd in how it reacts with itself. If you're sending Items back in the deck... you've just increased the odds your opponent will draw into more Items later (if the game doesn't end before that). Again, this could benefit the player using Ghetsis; the fourth copy might slam into an opponent's hand that has five Items... because the previous three kept shuffling them in before it was a good time to use them... or your opponent may have become so well adjusted by then they know that it is indeed good to "burn" some of those Items to avoid this scenario... or your opponent just pulls off a stunning, game reversing combo as they drop Professor Juniper and pull a killer seven Item hand, all useful at the moment.
The card is not broken because of how this format works; either players will reduce Item counts and the card will be strategic disruption... or it will punish the players who are relying on high Item counts, and frankly begging for such measures. In the latter case, if the game remains at its current pace, the times when Ghetsis scores less than three cards is going to hurt, because so often you would have drawn more or searched out something important.
This will become a very skill intensive card, unless players somehow manage to make the most crude decks dominate. That being said, it may not be something to run in high amounts, but as I also expect with Colress, one or two will become staples but more will be viewed as overkill. I think we are going to go back to players running a variety of Supporters; one or two near max counts of the more reliable with singles and doubles of the more specialized... since few are truly specialized but just seem that way compared to how generally useful key Supporters are.