Nixon was a President of the United States under investigation from several agencies and facing charges.
Vietnam draft-dodgers were facing criminal charges.
Weinberger was facing charges.
@Ghost Bear
Biden is talking about pardoning ordinary people who are not POTUS and are not being investigated, and have not been charged with anything. These are friends of his, people who may 'possibly' come under investigation at sometime in the future for one reason or another.
This has never been done before. This is legally defined as 'immunity'. It is not a pardon.
POTUS does not have the power to legally grant blanket immunity covering unknown decades just out of hand to any individual he choses. This is a completely different thing than a pardon. This is a new use of the power to pardon, a twisted definition of a pardon, which is being invented by the Biden Administration.
I am not a lawyer. I pointed out three cases where a Presidential pardon was given to people who had not been convicted of any crime. It just happened that those three had happened during my lifetime, so I was aware of them. I haven't done any research into the granting of Presidential pardons to know whether or not anything similar happened at any time previously in U.S. history. Have you?
We know that several of the people mentioned as possible recipients of a Presidential pardon are suspected of crimes: Fauci, for instance, lied to Congress regarding "gain of function" research. Millie possibly violated the UCMJ by refusing legal Presidential orders. Pelosi, Wray, and some others may have been involved in a conspiracy to allow the events of Jan. 6 to happen. None of the people mentioned are "ordinary", they are all people in positions of power who have been investigated by Congressional committees, which is how everything related to Watergate was found out, so you can't claim that isn't a real investigation.
By the way, on doing some reading about Nixon's pardon, I found out that for the pardon to be valid it has to be accepted by the recipient, and apparently the Supreme Court has held in the past that acceptance of a Presidental pardon amounts to an admission of guilt, so that's something. Also, since they can't be convicted of any crime they have been pardoned for, they can be compelled to testify in court. They have no claim of Fifth Amendment protection against self-incrimination, since by accepting the pardon they have already admitted guilt and can't be punished for it.
But I repeat, I'm not a lawyer, I'm just repeating stuff I've read online.