If the amendment can be repealed by statute, it can be "unrepealed" by statute since our government is not going to be in "progressive" hands forever.
Therefore, if progressives want gun registration and confisication, they must get 67 Senators and 38 states to agree to repeal the amendment.
Anything else will only be a disappointment to progressives.
Actually if the President is as smart as he thinks he is he would never have attempted this is the first place...
But...Yes, you are right, he do NOT have the authority nor the power to overturn the Second Amendment, much as he might wish! The idea that 2/3rds of the Congress and 2/3rds or the States would even consider overturning this is absurd. This is the problem with this Administration - they are either nuts or think that they can ignore the Constitution.
Hopefully, the Supreme Court will interdict or if that does not work due to Liberal opinions, the people will revolt as they should. It can and should not stand!