It's interesting how this affects play. If a player is bluffing slightly less than they should be, the adjustment is drastic, you should actually never call with hands that do not beat their value hands. If they are bluffing optimally, you are supposed to call using what is known as "minimum defense frequency". What's interesting about this is the minimum defense frequency is based on what the strongest hands you can possibly have in that situation are and the opponents possible hands do not even factor into it. It's required to prevent your opponent from bluffing with any two cards profitably.
To do the math, if you are on the river and the opponent bets 100 into 100, for this to be profitable for them they need to win 50% of the time or more. If your opponent is bluffing optimally, you need to call with 50% of the strongest hands you have in that specific situation (if you don't know what hands you have in a specific situation that's a problem) and sometimes they can be dogshit like King high.
But, very important to note, very few players actually bluff enough and if they bluff less than they should you should only ever call when your hand actually beats their range of possible value hands. (value vs bluff is kind of a difficult thing to communicate, generally it's value if you want your opponent to call)
Most players don't bluff enough as a result of most players calling too much! When they call too much you should obviously not bluff! This leads to very boring games of poker.