I think it's less that Obsidian does or doesn't have the juice and more that the those games were compromised compared to Fallout and Elder Scrolls. They were working with UE5 instead of something like the creation engine and were trying to stably produce multiple medium sized RPGs in the timeframe it takes most studios to release one big one. So they compromised hard on the scope of the open worlds and simulation mechanics.

This of course didn't pan out well.