I say this in the nicest way possible, but it is a very easy ship to fly and manage.
The design itself makes it very new player friendly, and for all of us, it's a good way to put points on the board. The front guns makes it so you just have to point the ship and shoot, and crewing one is also easy as besides the main engineer, the others aren't moving much. It has good stats for sustainability too, so it is forgiving of poor choices like splitting up from your teammate.
The gat/flak combo just culminated from its use of two front guns. It honestly is not the only combo that works up there, as I haven't used it since it gained popularity. People like it for its ease of use for the gunners, and results it provides in quick kills in comparison to other layouts.
I don't think it's OP in any way. It's something that works and has become popular over other strategies. While it does grow a little tiring seeing all pyras against you, they are not invincible. Their turning is slow compared to other boats, and they have perhaps the biggest blind spot of all boats in the game.
Of course, this is my opinion.