Thankfully, that particular map feature is not very common. As map-makers become more experienced and their tools become more sophisticated, the maps they design depart from the simple geometry of Fastest Possible Maps and become natural terrains where each movement is the sum of hundreds of choices. To better understand how styles of players have shifted and will shift, we should look at history of the Battle.net Ladder map designs to see which map features have gone out of favor and what features continue to be popular.
One of these disappearing features is the Main Base Backdoor. Seen on maps such as Blistering Sands and previous versions of Shakuras Plateau, the Backdoor was vehicle for crippling blows or time-saving distractions. Coupled with a distant and vulnerable natural expansion, that exploitable entrance could make attempts to defend extremely difficult. In the case of Shakuras Plateau where the Backdoor also led into a narrow corridor, armies grouped in the close unit stacking benefited incredibly in the Backdoor while a defending army without splash damage was far less robust, even in its own base. Currently, no map in the Battle.net Ladder Map Pool, GSL Map Pool, or MLG Map pool contains this feature. Even Shakuras Plateau was altered to remove this.
For the record, the Zerg won that battle!
Another kind of formation that has not been utilized often is the Ranging Ledge. Somewhat difficult to name, this type of terrain is a ledge where ranged units would be able to attack harvesters or buildings in the main base or natural expansion with relative safety. The Ranging Ledges include plateaus that are adjacent to bases, or jutting terrain separated from the base by some sort of gap. With superior range granted by abilities such as Siege mode for Siege Tanks and the Tac Nuke Strike from the Ghost, Ranging Ledges provided incredible safe zones for the attacker that the defender would often fail to recognize. Delta Quadrant and some portions of Taldarim Altar LE possess this feature. Others that had this type of terrain were Kulas Ravine, Lost Temple, and previous versions of Desert Oasis. Map Makers who plan to have multiple layers of elevation while avoiding those Ranging Ledges often fill these high areas with doodads to prevent units from dropping.
And people thought Thor rushes were the thing to worry about; 30 seconds later two more vikings come.
Oddly enough, there is only one island expansion that exists in the entire Battle.net Ladder Map Pool which is located in Scrap Station. The Island Expansion alters game play in that flying units/drop play or Nydus Networks are required to even threaten this source of income. Static defenses of these areas are favored because any defending force would be removed from any other battle while taking up Supply. With only a ground army and no specific investment in Nydus Networks or Drop Technology, many players will not be able to make use of these resources or threaten an attack on one. Previous maps that held these features such as Desert Oasis and Lost Temple have been updated to include these prodigal landmasses or have been removed from the map pool.
Hah, your Tier-1 Tech Fu is no match for my Tier-2 Stance.
Whether or not these map features should have been phased out is a subject that requires more experimentation before any conclusions can be drawn, With the incredible variety in playstyles seen, the removal of a single island or destructible rock may feel inconsequential in the long run, but for those who have built their entire play around these specific map features, the removal of these terrain varieties may be cause for sighs of relief or nostalgia for a tactic that was ahead of its time.
Edit: Whoops sorry about the images. Fixed thanks to comments!
Credits to HuskyStarcraft for the games I chose to screenshot.