No, but Baldur's Gate also made sure to design a campaign that a party of 4 Fighters could clear. For example, you don't have to put on a disguise or something to infilitrate the enemy strongholds, your tadpole takes care of that. Or later when you need to infiltrate a devil's domain in Hell, there just so happens to be an NPC that . In other words, Larian never has to "build a bridge" because they thought the game through at the outset.
But let's say they didn't think of that, and it was a tabletop game. How hard would it really be to create an NPC diabolist who can get you into Hell if one didn't already exist, using a ritual that the PCs have no way to replicate on their own? Because for me, that would be extremely easy. And the players still have agency because they can simply decide not to go (and deal with the consequences later.)
Okay, name them. No, really.
Like maybe if you don't have someone who can fly, there's a treasure chest you can't reach or something. And even then, scrolls exist. So I have no idea what you're talking about.
EDIT: The druid holes don't count, literally everywhere that has one has other means of getting into or out of that area, so no, try again.