I think number one is definitely wrong. Recent inquiry led reviewers to discover not all boards are created equal. While differences aren't drastic on some boards you can't reach boost clock written on the box.
Even if there were more serious issues, I would argue that AMD did the right thing keeping the AM4 socket. Since this varies from board to board, it's obviously not a deficit of the socket itself. At the end of the day, nobody is forcing you to keep your old motherboard. You just have the option to. If you can save 25% by not buying a new motherboard, it probably justifies a small performance deficit.