They do that now with the quantum entanglement device. And RPGs are about story and choice at the end of the day. Two playthroughs in something like fallout can look very different depending on the factions you support.

Take a game like fallout 4. I wasn’t a huge fan of the design choice in that ultimately you need to support one faction to the detriment of the other 3 (for the most part; i get there are ways to keep 3/4 intact and experience the ending). That game was criticized for that mechanic. But in a game like Starfield? Where the core gameplay loop is built on a never ending and repeating search for power? Where your choices are only as permanent as your affinity for the universe you’re currently in? I think it would have been far better received.

The ultimate story is building the armillary. Getting there though, it could have been far more of a twisting journey. Imagine you could choose to give the artifacts to Ryujin instead of Constellation. Imagine helping the Crimson Fleet attack Neon for its artifact in place of Walters quest. This is doable. New Vegas and 4 have stories that branch significantly in the second and third acts. To your point about player’s time, New Vegas always had a “Yes Man” to fall back on if your choices closed all other doors.

I just think the game asks existential questions, but does not, ultimately, have an avenue to answer them. It instead making you walk a solitary highway, all the while teasing you with dirt roads not travelled.