If you didn't play the games and just heard about it in passing you wouldn't be irritated by the lack of various qualities that made the game series good or the misplaced things and would enjoy the plot I suppose.
It follows the story of the three main characters and their family with flashback scenes to prewar giving insight into how the vaults were made.
There is not much emphasis on the morally grey choices you find alot in fallout game series plus there is a lack of immersion you get from those dilemmas it doesn't feel gritty enough.
As a person watching that has followed the game it's not a bad attempt but doesn't capture the feeling of the game dialogue at all although a fair amount of attention to detail has been achieved with the set and effects it still feels off for some reason.
There are some big mistakes with fallout lore things are not correct for the time it's set so I assume they are rewriting fallout history to fit the storyline.
The acting was sub par and corny at times they missed the opportunity to bring the dark humour the fallout game series has always been good at. Hopefully they can improve upon it next season.
All in all still a good series worth watching but if you're a hardcore fallout fan you may be irritated by this series for various reasons