Both of your posts are based on logic that falls apart under a little scrutiny.
First, the US (either the President, SOS, VP, Ambassadors and others) both Democrats and Republicans have denied or threatened to deny aid to foreign governments many times for a variety of reasons in the past. It is not illegal. Second, Trump didn't tie the aid to the request, he merely asked them to investigate corruption in their own country. Read the transcript: he did not make any reference to withholding aid in the conversation. The aid was transferred as scheduled. By the way, quid pro quo was first used by the Dems and then dropped because their own witnesses said there was none.
By your definition what Biden would also be guilty of bribery and extortion. You can't have it both ways; either Biden is guilty of bribery and extortion, or neither of them are.