Then you are saying there should have been an Amendment to legalize interracial marriage throughout the country because even after the 14th was put in place, interracial marriage bans were ruled not to violate the Amendment. The same for segregation. So, I guess you believe that that too should have had an Amendment to address it?
It is the job of the SCOTUS to interpret the Constitutional Amendments. They exercise at least some restraint in doing so but everyone will complain about something or other.
We should not have to put every single right that the states or federal government should not be allowed to abridge in the Constitution. The Equal Protection Clause of the 14th is actually a pretty good Amendment to ensure that people are treated pretty fairly, particularly those who can show they are "similarly situated" in regards to other groups, but they are being treated unequally. This requires the state to provide the rationale for why it feels it is in the state's interest to not treat those two groups equally. The Constitution is meant to limit the government and the laws of the government, not say that the citizens are only allowed to do what is specified in the Constitution.