It depends on the time of day honestly. The later the opening the longer the line seems by the time they open the gate.
Normally they let people in 30 min prior to regular park hours to wait at rope drop and it can vary. I have been at the end of Main Street by one rope or at different ropes for tomorrow land or fantasy land. DCA rope drop I’ve only seen multiple ropes for each area.
I like to get to the park to be mid rope drop. Honestly unless you are there for MM and can just fly through the gate to a ride, it really makes little difference if you are up against the rope vs. several rows back and if you can walk fast you can pass a LOT of people from gate to rope and beyond.
We used to show up stupid early as my DD loved being right at the gate, which is great for MM but unnecessary for rope drop and any time we saved in line for the first few rides we paid for with all that time waiting early at the gate.
This trip, we will likely show up to security around 8:30 for 9AM openong to as to be through the gate and into the park by the time they drop the rope, and if it doesn’t work out we’ll adjust accordingly.