But wouldn't it be a better design if you managed to have the best strategies also being the most fun to play? And just like there is no guarantee that players find the best strategies, nor that they find the most fun strategy. Maybe they stumble upon something that works, and realize it's unfun,but how are the supposed to discover that the worse options will be more fun in play? Once you know certain tactics or abilities work well, it's hard to consider the worse options, because they look worse, no reason to believe that they could somehow be more fun.
Only in the aggregate of something like a forum where gamers of different gaming groups meet and exchange their experience they might discover ways to make the game more fun.
 Especially since it might require an understanding between player and GM that the opposition will be built around the players not using the best options - if not, they might just experience more character deaths, failed adventures or TPKs because the DM - after having seen what they can do once, or because he saw the same potential - expects them to hide in Secure Shelters and strip off legendary resistance to stun-lock the big bosses or whatever the game in question has as its most effectice strategy.