That hasn't been demonstrated. It could be that when the decision was made to offer free/unlimited storage, there were beliefs about the economics of that option -- particularly, the rate of change in durable storage pricing and performance -- that ended up not being borne out. (I am not privy to any special knowledge about this, but it is at least plausible based on how the storage business had been working for the years leading up to 2015.)

I agree in general that teaser rates -- as opposed to well documented free tiers -- are at best a gray area.

Additional data could be considered more of a liability than an asset, as it's more data to protect and store and more data that could potentially be exposed in a breach. Likewise, it may be good to lose users who aren't paying but are storing tons of data with us -- which as we've already established can be thought of as a liability. It's good to have a free tier to show the customer the value we can deliver, but if the customer doesn't get enough value from us to pay the (IMO very reasonable) prices for what we're offering, then maybe they would be better served with a different provider -- at least for bulk photo and video storage. This is not a bad thing, IMO.