I've only recently started following Alter's writing on Treehugger, and find most of it very insightful. With this book, I was skeptical going in that I'd agree with his central thesis, but hoped I'd still get something valuable along the way - and I think that ended up being the case.
Alter's position and mine probably aren't worlds apart. I would say individual action matters, and we as people committed to climate action should do what we can on an individual level - but collective action and systemic change is going to have much more impact. Alter would agree that collective action is important (and he cites examples of how he does this) but makes the case for why he thinks individual action is more important than many people think. Both important, just a question of emphasis - so not a million miles apart.
But the problem with Alter's emphasis on individual action is that he never really addresses the core problem, which is how to scale it. Yeah, if everyone on the planet used the power of their consumer choices to reduce their carbon footprint, that would help a lot - the problem is most people aren't doing that at the moment, and probably won't do it unless we make those choices easier for them. The crux of the "individual vs collective action" debate isn't whether the small number of people fighting for climate action should try to reduce their personal footprints (the answer, obviously, is yes) it's whether they should spend their time and energy trying to convince others to take individual action, or to spend that time and energy pushing for systemic change. Alter does not attempt to address this question, or even really acknowledge it exists.
With the result, his case for why individual action should be a higher priority is flimsy at best, and it makes some of his recommendations pretty weak too. He quite rightly talks at length about how transport and land use and energy are all so intertwined as to be basically the same thing described in different language - how our transport emissions depend on the urban planning of our home, and how that same urban planning can affect the size of the fridge we need, and so on - and his grasp of this and eloquence at explaining it is really fantastic. But then the end-of-chapter recommendations come, and he says "Choose where you live carefully; it is the single biggest influence on how much you drive." But of course, with a focus on individual action that's a zero-sum game; there's only a small amount of housing stock in North America that has good mixed uses and walkability, so that choice is only available to a small and finite number of people (and because of limited availability, probably relatively rich ones). We could have a lot more housing like this, if we fixed the planning regulations that prevent new suburbs like this from being built - but individual action will not make that happen, it requires collective action for systemic change.
This kind of dynamic appeared a number of times throughout the book - Alter genuinely has a fantastic grasp of the problems, and to be fair a lot of the time he really understands the solutions too, and makes some good suggestions. But his attachment to individualistic action is a huge blind spot, and it gets in the way of the real solutions over and over again.
Anyway. Like I said, he does have a fantastic knowledge of the problems, and I took away some great bits and pieces that will help me do my bit in the fight against climate change. Knowing where the big fish are and what's too small to bother with is valuable, regardless of whether you're thinking individually or systemically - and I'm completely onboard with his argument that we should stop using the term "embodied emissions" and instead say "upfront emissions". So overall it was definitely worth the purchase price for me.