I think the sentiment here is one worth talking about. Having a collective set of standards as an industry is good for everbody.
But some of the examples aren't great ones. A plumber can't sell his services for 1$ because his services don't scale infinitely with no additional cost. He is selling his TIME and expertise. If you sell a set of icons, that extra sale doesn't cost you any time above your initial investment.
A better comparison is to ask if the plumber would sell an e-book of best practices for a couple of bucks. My guess is that he would if it gave him exposure and some passive income.
I remember reading this article when it first came out. Here's what I got out of it:
You can pay very little for a service or product, and it will probably not do the job very well, possibly just good enough to get by. OR, you can hire someone with expertise to do a good job, based on both their talent and expertise.
Design is seen as a commodity that is worth nothing because designers are the ones who have taught people it is to be treated that way. Any other service professional would never do what designers do regarding price...they could not survive.
Open source projects are awesome when they happen. I'm thankful for things like WordPress, Font Awesome, Bootstrap, etc, because they help everyone build better sites. But there is a cost behind those projects. Those projects cost a number of people a lot of time. There has to be a reason behind that. Whether that reason is a side business related to the product (Automattic), exposure (icon sets) or if the company has a lot of time to spare, just a way to give back to the community (Bootstrap), I guarantee you these projects are not for nothing.
There has to be revenue at the end of the day from these projects, in some shape or form.
Regarding charging a decent rate: Designers SHOULD get paid for their efforts. It's stupid not to. This is not artificially raising the cost of the industry, it's putting it where it always should have been in the first place.
So things like The League Of Movable Type, Bootstrap, Font Awesome, Unheap are devaluing design? I really, really can't agree with that. Why is open source good for the engineering that goes into software and websites, but bad for design?
There are services that make it cheap and easy for people to make websites? Awesome! That's great—it's called democratization. As a designer, that should inspire you to raise the bar, to make even more amazing things that can't be done easily or cheaply, not to bemoan the fact that you can no longer rely on the same things you've been doing for the past ten years.