It has been said by many that total GP is not sufficient for matchmaking. That it should take into account such things as zetas, gear levels, mods, and even specific meta characters.
The two images below clearly show me beating my opponent and our stats. He had 8 more zetas, at least 16 characters with superior gear and multiple meta teams that I don't have (traya, zbastila, NS). Yet I still came out on top. I strategized over the last 8 hours seeing what exact teams I would need to beat him and it pulled off (all fleets have been used)
Ultimately zetas don't win matches, characters don't win matches, and gear doesn't win matches. Good players win matches.