Alfie Kohn is one of my favourite writers and this is a good example of why. Kohn's basic concern with personalized learning is that  "Each of us can do what he likes as long as he ends up fundamentally similar to everyone else" but he drills down a lot further. These are his fundamental worries with how personalized learning is being conceived and implemented:

1. The tasks have been personalized for kids, not created by them.

2. Education is about the transmission of bits of information, not the construction of meaning.

3. The main objective is just to raise test scores.

4. It’s all about the tech.

I share Kohn's concerns - I am appalled by a lot of the adaptive hypermedia, learning analytics and intelligent tutoring systems that I have seen, dating back around three decades or more but apparently now reaching critical mass in the personalization movement. He is absolutely right to be afraid of how these things are being used and implemented not just for kids but for adults. The trend towards measurability, uniformity and control of students is a heinous crime against this and future generations, made much worse by the institutionalized power abuse that comes with the package.

On the other hand, I think that it doesn't have to be that way. First of all, it is important to consider the granularity: adaptive systems can have a lot of value when they are available in small pieces that give learners the power to choose them as tools to support their personal learning (and, as Kohn points out, social learning). I am also not averse, on the whole, to tools that suggest and advise but that do not dictate. But mainly, like all things technological, from painting to bridge construction, it ain't what you do, it's the way that you do it that matters. It's a problem when the process of learning is hardened into a toolset that is dictated by a small hierarchy and not socially negotiated. It's the higher levels of control that are the most worrisome technologies in this assembly: the tools just make it easier to exert that control. We should fight against the standardized tests, the teaching for grades, the manipulation of learners for political ends. But, when that toolset simply adds to what we already have, it can make the whole system more creative, flexible and controllable by learners. It's the difference between what Franklin calls 'holistic' and 'prescriptive' technologies.