Earlier quoted context omitted.
This is what dark patterns rely on, why the hell would you be in support of companies taking advantage of people? Have you never had anything like this happen to you? Maybe you were tired or in a rush and a dark pattern ended up costing you money you didn't intend to spend? It's happened to me, and I'd dare day most people reading this.
I use this product and this plan. I knew what I was getting into when I bought it. Scammy companies shouldn't be protected, but if people don't bother to do the most basic due diligence before buying products, it's on them - like forget reading a terms of service. He doesn't even read the product name or description. Gets into a yearly contract for a cheaper price and then complains about the cancellation fees. At so…
It is a basic necessity for beneficial trade to occur that the terms are made clear, not just technically available, to the people potentially wanting to undertake that trade, before anything legally binding occurs. The issue is not that there are cancellation fees, it's that they are not made clear.
The exaggerated, but still representative, example might be the Earth demolition plans in Hitchhiker's Guide, which were "available for 50 years in the local planning office in Alpha Centauri." Totally fair, right? Anyone could have just gone there and read them.
Demanding "personal responsibility" as a solution to avoid bad deals is the same as accepting that it's OK for some people to be scammed. No one is perfectly on guard all the time. If it is permissible for companies to engage in scammy behaviour, and scammy behaviour increases profits, then in order to be competitive, companies will engage in scammy behaviour. So it will be everywhere. Since, as noted, individual humans aren't perfect all the time, eventually someone will get scammed.
The obvious, morally superior, and more economically beneficial solution is simply to not allow scamming to be profitable. That, among other things, means ruling in favour of the consumer when companies perform shady practices.
Postscript: People with this kind of "libertarian" stance really annoy me. To give the benefit of the doubt, I'll assume that "personal responsibility" isn't just thinly veiled personal exceptionalist elitism. If that's the case, the only reason you can even have these beliefs is because you take so much about the modern world for granted. There is a lot going on in order to create an environment where mutually beneficial trade can happen.
In the absence of strict, neutral enforcement of fair trading rules, people scam the shit out of each other. It's way easier, and more profitable, than actually creating something of value that people want to buy. The total effect of this, if it were allowed to occur, is that it creates an environment of distrust and uncertainty, which means mutually beneficial trades that would otherwise happen won't happen, making everyone poorer. Advocating for "personal responsibility" as a solution to avoiding scummy business practices is directly advocating for this situation.
Historically, before commercial law was explicitly codified, the means of ensuring that merchants were trustworthy was essentially reputation. The way this scaled was with merchant groups, where the reputation of one member going bad affected them all, so they all had incentive to police each other (or alternatively, collude). Plus the fact that people in general were much less dependent on markets for necessary goods, the labour force being mainly agricultural. However, this made opportunity for trade highly exclusive, and largely only available to the privileged ("merchant class").
I guess my question for you is, do you want to have to read every single EULA, thoroughly scan the terms of every transaction every time you buy something, and otherwise do a lot of work and research any time you have to make some vaguely commercial agreement to avoid getting into an agreement you, in retrospect, didn't want? If not, I suggest you carefully re-examine your beliefs and what they imply.
A final remark. The economics of scamming are highly asymmetrical. If individuals have to do a lot of due diligence even for routine transactions, that is a massive cost to that individual. In contrast, organisations willing to partake in scummy behaviour can spend almost endless resources optimising their ability to ensnare customers, because once the process is developed, the marginal cost is very low if not zero. So individuals cannot be expected to "keep up" in this environment.