JFYI, it is only the English/American that use quid pro quo in that sense, in Latin (like in many other languages) it has a different meaning, while do ut des has that meaning:

https://en.wikipedia.org/wiki/Quid_pro_quo

"The Latin phrase corresponding to the usage of quid pro quo in English is do ut des (Latin for "I give, so that you may give"). Other languages continue to use do ut des for this purpose, while quid pro quo (or its equivalent qui pro quo, as widely used in Italian, French and Spanish) still keeps its original meaning of something being unwillingly mistaken, or erroneously told or understood, instead of something else."

I think all Americans know what "quid pro quo" is. A President was impeached for that. It was most likely the impeachment of the century.

You are overestimating the average Americans. I can assure you 90% wouldn't know what it is if you ask them.

Trying is free, ask your friends tomorrow and share the results here please.

Many Americans have heard of it and know that Trump was accused of it, but might not know what it means. And not everyone on this site is American.

The literal meaning is "what for what?".

Not really. quid/quod can mean `what' or `something'. Here it clearly means `something'.

So kind of like a "something for something" ?