Someone please explain what being Sephardic or Ashkenaz has to do with anything?”
If by “anything” you mean shidduchim, the only relevance is that some sephardic and some ashkenazic minhagim differ greatly (most notably at Pesach time), and that might bother some people, especially if an ashkenazic girl marries a sephardic boy and must take on his minhagim of eating kitniyos.
There are also some social/cultural differences, I have noticed in some friends, but that is still up to the parties involved to see if it will be an issue for them. Some of those differences are more of an issue than others. Many people embrace these differences and very successfully blend the two cultures.