The Towers maintain stability... but not of Mundus.

If you consider what a Tower is, it's clear that it's important. They're huge, they're tall, they're iconic. They're symbols. And it's been said that they help advance order in the face of entropy, and hold all of creation together. That, my friends, is false.

The simple answer is, Towers have no metaphysical significance in a mechanistic sense. An "active" White-Gold does not maintain the stability of continents (if such things exist.) Rather, they are, if you'll pardon the pun, social constructs. Each Tower represents the finest flowering of any given society or civilization on Nirn Let's list off some of these, shall we?

• Red Tower: The Tower of the Chimer/Dunmer. Prior to the Tribunal, the Chimer followed its Stone out of Aldmeris, and founded their civilization where it fell. It was, in essence, their establishment as a true people group, a true, distinct, respected culture. Post-Tribunal, the Tower became the (perhaps unwitting) center of the entire Dunmer culture, by uplifting their living god-heroes. When the Heart was unbound from it, in essence when the heart was ripped out of their civilization, the golden age of the Tribunal Dunmer ended. Morrowind was ripped asunder by eruptions, invasions, and calamities. Society, to an extent, thoroughly destabilized. Deactivated, painfully.

• Crystal-Like-Law: The Tower of the Altmer. The most direct parroting of Ada-Mantia, Crystal-Like-Law represented their commitment to stasis, and preserving the old at the expense of the new. Under its light, Altmer culture flourished and thrived in bureaucratic, aristocratic, insufferable glory. When the Daedra demolished it during the Oblivion Crisis, that spirit of maintaining the status quo and being a city on a hill vanished, in lieu of Thalmor conquests, cullings, and chaos. Altmer society darkened with the elimination of Crystal-Like-Law. Deactivated, and smashed into disorder.

• Orichalc: The Tower of Yokuda. Orichalc's Stone was a sword, and it was by the sword that Yokuda fell. Little is known of the specifics, but the fall of Orichalc and the fall of Yokudan civilization itself are bound up with one another. Deactivated, and lost.

• Green-Sap: The Tower of the Bosmer. Perhaps the most direct attempt at changing the branches by altering the Root. Green-Sap represents the mercurial nature of the Bosmer, and their lives of happenstance. Anumaril, in exposing Elden Root's Perchance Acorn to his imitation of Tower One, tried to turn Green-Sap into White-Gold, and in doing so turn the Bosmer culture into a new Ayleid empire from within. However, the multitudes of Perchances made this task particularly impossible for him. In the present day, I believe Falinesti itself has ceased walking because it has fallen in step with the new Dominion. The trees are not wandering, but rather there is one purpose for all Bosmer, and it is doom. Maybe not deactivated, but supplanted.

• Snow-Throat: The Tower of the Nords. "When the Snow Tower lies sundered, kingless, and bleeding." This is not some mere reflection on metaphysical stability in Skyrim. Snow-Throat is the spirit of the people. Skyrim is sundered, kingless, and bleeding. Its society has not completely collapsed, but without immediate triage, it will, and Snow-Throat will fall. The pride of the Nords, which has, by rights, survived since the first Tongues who hurled Alduin from the world at the very summit of Snow-Throat? It will be broken. Not deactivated, but fading.

• Walk-Brass: The Tower of the Dwemer. An interesting one, because depending on your interpretation, this might be a Tower that carries the population with it. Walk-Brass' entire reason for existing is to uphold the Dwemer believe of "YOU ARE NOT," to the point that the Dwemer themselves are not. It's Walk -Brass because Numidium is representative of a culture that severed itself from the world, and so it itself is severed from everything else. It's personified anarchy. Not deactivated... yet.

• White-Gold: The Tower of the Ayleids, and later the Tower of the Septim Empire. White-Gold shows us that the Ayleids were too crafty for their own good. Not only is it representative of their culture (shining, white stone capped with brilliant gold, built on land in the middle of a vast lake) but it shows their willingness to bend their culture to achieve their own ends. White-Gold is built in the shape of the Wheel, the Universe as we know it. This apparently gives it control of creation, and makes it the seat of kings. One Red Ring to rule them all; all Empires that conquer other Towers are supported by White-Gold. Under the Ayleids, I'm not sure what the Stone would have been. Maybe it was its own stone. Either way, when the Ayleids fell, White-Gold was taken by the Nedes, later Imperials, and they made their stone the Chim-el-Adabal, the jewel in the Amulet of Kings. The Emperor became the focus of Imperial life. When the Emperor was gone, and the Amulet of Kings was gone, White-Gold finally went silent again, and BOOM. Interregnum. Even now, the Mede Empire has trouble contending with Tower-based cultures, because White-Gold is not behind it. Deactivated, but perhaps not forever?

• Ada-Mantia: The Tower of the Aedra, whose Zero Stone is hallowed Convention. As long as it stands, and as long as what it stands for stands, the world will continue. All other Towers ape its purpose, because this one Tower is the one that symbolizes the calling of the Aedra and the Earthbones to keep the world together. Active, and wrought well; largely untouchable, even.

In summary, the only Tower that holds Mundus together is Ada-Mantia, because it is the Aedra Tower. All the others use its power to symbolize a cause and a culture, and to call what are essentially et'Ada together to create something bigger than themselves. Each one is unique, but no more unique than their respective cultures are. It's possible for those cultures to change. The Ayleids are dead and gone, but their Tower, their culture and status, were just appropriated and supplanted. The same has been attempted with Green-Sap at least once, probably twice. So, yes. They're social constructs, in that they are constructs that hold societies together.