I like this post, it's clear, well considered and concise. I'd caveat that with, "for certain kinds of companies". Two thoughts:

1) On his issue with levels. I don't disagree with most of the observations, but I've definitely experienced staff that are less concerned with the pay increase and just want the validation and pat on the back of the level bump. It's weird, because it usually comes with more responsibility and work. While just getting more money lets you go back to what you were doing and are already good at. But everybody has their own ideas at career progression.

2) In my personal career, the types of companies I've worked for have a slightly different flavor of this, and I've come up with my own internal shorthand ideas for what these titles mean. It's useful to consider this because as you rise in these ranks, you have to also train the next generation to be able to step into your shoes and do a good job:

Manager - you are 85%/15% focused down/up. Down into your reports and tasks and up to receive new input from your manager (perhaps a director) and provide back status. You spend that 85% of the time taking somewhat vague directions and turning them into actionable tasks by your reports. You reports in turn should have well scoped tasks that when completed, build into a completed work unit that satisfies a directive from up your chain. You are a work breakdown structure and scheduling engine. Your performance is generally measured by delivering programs on-time, on-budget, and having a minimum of issues with your reports.

Director - you are 50/50 focused down/up. You spend time refining vague business unit goals into vague programs. You rely on your Managers to turn those programs into work tasks. You have a lot of responsibility for driving revenue, have a budget, but in most companies are not specifically measured by P&L. Your performance is measured by revenue targets. You get pulled into sales and marketing projects that are already moving freight trains to provide grounding, and to mobilize resources under you to support specific efforts. You got into your position because you provided on-time, on-budget program successes repeatedly, and a few of them struck gold by chance. You also had a knack for working well with the sales/marketing people and maybe even straddled between worlds.

VP - you are 15/85 down/up and spend that time turning impossibly vague corporate goals into merely vague business goals. You are responsible for P&L, and your performance is measured by both revenue and profit targets. You spend a lot of the day working with sales and marketing, and you conceive and initiate growth efforts. Depending on the company, you likely have your own subordinate sales and marketing team that reports directly to you, and is separate from the engineering team. You got into your position primarily because you are really good/lucky at growing revenue and can put together revenue growth strategies that have a higher probability of working than not. It's even possible you never spent time in the engineering organization, and worked up through the sales/marketing path.

Source: Been all of the above at various times. Highest position was President of a very small startup, which I count as almost meaningless (where I also did a stint as a VP). "Biggest" position was half a decade as a Sr. Director of an 200+ head engineering organization in a several thousand person company till I was promoted out of it.