It's probably because defenders kind of get boned in it so to say...
1st set of objectives:
A = destroy small building
B = destroy small building
2nd set of objectives:
A = spam grenades and plant, continue spamming 40mm/CG/nades/etc...
B = destroy medium building
3rd set of objectives:
A = blow hole in back of building, plant, nade spam defending entrance
B = This is the only objective you can actually defend against a team using the above strategies because the building doesn't collapse and nade spamming isn't as effective due to a wide open area around the comm station.
That isn't to say you can't prevent these things from happening, but any well-coordinated attacking team is going to win the first 2 sets of objectives regardless (potentially failing at 2A but doubtful). Defending team could be godlike and still end up turtling B on the 3rd set.
I personally enjoy the map, but I can understand why people would hate it given the above.
