I can see the advantages of having gates dedicated to particular carriers and pre-assigned to a particular flight which uses the same gate every day, particularly at the busiest airports.
However this system which is in use at most US airports can be annoying for passengers when the assigned gate is occupied and you have to sit waiting for however long for it to clear when there are plenty of free gates. If an aircraft lands at MAN
for example and the planned gate is occupied a new gate will be assigned before the aircraft even reaches the terminal. If though this was a Delta flight at MDW
for example, and their only gate (C3) was occupied there would be problems and long delays whilst another gate was sourced.
Dedicated gates are good when they work, but when they don't ...