I wouldn't call this “proactive” any more than trust busting in the 20th-century USA, nor for a more recent example the introduction of the GDPR. Abuses are occurring now, so society saying “actually we don't want that to happen” would be reactive regulation, in itself, even if the forward-looking side effects are debatable. To be clear, I'm not sure what I think about the possibility of dismantling network effects by legislation at the current tech level; it would depend a great deal on specifics, and I certainly think the idea in general has a lot of potential downsides—but not enough to make me immediately reject the whole thing, thus the speculation. I note especially that some of the aforementioned trust busting involved the abstractly similar case of the Bell System.

The bifurcation-chaos that intuitively seems to surround network effects makes for an interesting fork here, actually (assuming of course that my intuition is anywhere close to correct). Both sustained overreaction and sustained underreaction can get very bad. Looking at the earlier example, earlier communication grids' network effects were more dependent on physicality, and “everything is ephemeralized as software with effectively unstoppable automatic updates” is a huge lever in both speed and dimensionality of power. So maybe the meta problem of “legislation can't operate as a control system with enough bandwidth to keep up with technology businesses wiggling the cable to get what they want in the grapple for the ‘humanity's nervous system’ role” is more important here.

Or, perhaps, human societies decide that technology level exceeding value reach is so undesirable that the innovation explosion becomes a casualty of preserving humanity's nature, because the alternative of it eating into everything faster than it can respond (which I would say is what is happening now) is worse, and then we get Dune. Or perhaps we designate sub-areas of society as experimental zones, regulate the heck out of the stable zones, and get closer to dath ilan…