If you are to compare stuff, stuff like modern razor cartridges and double-edged razors, you ought to mention the convenience side of the things. I hate being the devil's advocate, but shaving with 4-blade cartridge designed for easy shaving is still 'miles' ahead compared to shaving with double-edged razor. Miiiles ahead. And I use a double-edged razor 9 out of 10 times, so I would know a thing or two about it.
And that's not to say that are overly pricey. They are. Plus, if you account for different prices in different regions, the price difference is even more concerning.
The same is also true for some other appliances/services mentioned - tea bags and coffee machines are not just 'superficially convenient' they are wildly more convenient.
EDIT: As one person said in the comments down below, "What this article completely misses, is that there are more than two options.". That was my whole point, and I'm sorry if it came out the wrong way. Shaving is a personal preference, and you are free to do it however you like; but saying 'Shaving is too expensive and is a demonstrative example of how most consumer products are designed to extract more money from you rather than to improve your life, or the world, or to be in any way remotely good.' is just incorrect and insane.