Mecca Gate is one of the smaller historic pieces in Bijapur's fort landscape, easily overshadowed by the Gol Gumbaz, Ibrahim Rauza, and the city's great mosques. That is exactly why it is useful: it helps fill in the defensive and urban fabric around the famous Adil Shahi monuments.
Do not cross town only for the gate, but include it if you are already tracing the old walls and religious buildings. Bijapur rewards this kind of wandering, where a modest arch or battered wall suddenly connects the headline monuments into a city.