1) sometimes AIs are nice and dont want to steal, living you with agent recruits for the rest of the game
2) sometime you have so much money that benefit is insignificant
If you have a huge tech lead, and you have so much money that there's no point in rigging city-states, and you're bored with the lack of espionage options, then go up a difficulty level. If you're already at deity, then play multiplayer.
What fyar said. Basically, when you have an overwhelming lead in X element of the game, ANYTHING that contributes to X can be viewed as superfluous and useless. This does not expose a problem with X.
If you have a huge tech lead, then certainly, stealing techs is going to be useless to you. If you have more gold than you know what to do with, then certainly, rigging CS elections will be of little to no benefit to you. The complaint that
is flawed; there are things to do. Just, they aren't particularly helpful in this specific situation -- and that is as it should be. It is an inevitable byproduct of the player's commanding lead. A player who has both a huge tech lead and enough gold to do anything s/he wants will very rightly not have much to gain from espionage. Noting this does not reveal a flaw with the espionage mechanic.There should be things to do with espionage when you are the leader