In a 4-player Standard campaign, I always start my deck with 3 of these, and remove them somewhere before the halfway point of the campaign, and it works out well for me each time.
To start with the upside, if I draw 2 Open Gates, it routinely saves the group 3 actions a game, sometimes less, frequently more. In most campaigns' early missions, you're in the "explore" phase of the mystery, where you are wandering around town/campus/jungle flipping locations and collecting clues. Since you're low-xp characters, you don't have much of your jank, but the game accommodates you with easier shrouds and monsters, many of which are beatable with just base stats. It's usually effective for your group to split up, but there's always that Act that says "investigators at <Location X> spend clues as a group to advance/resign", where the party has to get to a specific spot. Open Gate lets at least one teammate teleport there, which may even let you advance the Act a whole turn sooner than you could have otherwise.
As for the fail cases, If I draw 1 Open Gate early but never get its partner, then I'm out a card and resource, which is a fair price for a failed gamble in this game. If I draw it late, I can pitch it to a treachery. It may be suboptimal, but it's never dead.
The card definitely gets worse as the campaign goes on, both because missions start to become "charge forward to your inevitable doom" with no backtracking, and also because your bottleneck changes from movement action economy to succeeding repeatedly at difficult tests, and Open Gate doesn't help with that.
Like Flashlight, I think this is an excellent level 0 card for your starting deck that you swap out later as they become obsolete.