I think pointing out that virtually all the (near-) monopolies we see in the IT market place are (naturally) used to extract significant rent, that this is a canonical case of market failure and demands some sort of corrective is a valid point to make when yet another market sees a player trying to establish themselves as such a monopoly.
I can totally point out that in similar situations, the result was a market failure, and that it might be good to do something about that before it happens again.
Now, to put up a straw-man against that, why not wait to see, usually these platforms fail pretty quickly anyhow?
Well, if the outcome is either failure of the platform, or success of the platform by capturing (nearly) all of the market, then why no regulate it?
