Let's define three variables with which we want to characterize knife sharpening tools:
- The best possible end state of the knife if the tool has been used expertly
- The worst possible end state of the knife if the tool has been used improperly
- The amount of effort needed for a person to go from "have never used it" to "using it expertly"
The first thing you have to recognize is that these three variables are independent of each other. The second one is that the evaluation doesn't somehow reverse for different kinds of knife - it is not that the type of knife doesn't matter, because an expert with a whetstone will get a worse "best possible result" with a cheap stamped knife than with a quality knife. It is that, if tool A performs better than tool B in one of the three dimensions on a quality knife, it also performs bettre in one of the three dimensions on a bad knife (there are exceptions, but I don't want to go into deep details here).
Now imagine a three-dimensional space spanned by the three variables (I don't have a way to draw it easily for this answer). It is important to note that it is not a single quadrant - so if the initial state of the knife is at zero, then the worst possible state for some tools can get into negative numbers.
The traditional system of a sharpening stone (or a combination of sharpening stones with different grits) and a leather strop for honing is at one corner of this space: It has a higher "best possible result if expertly used" than all other tools, a worse "worst possible result" than all other tools, and a higher "effort to learn" than all other tools. This makes it the best choice for afficionados - they happily expand the effort to learn and stop caring about the "worst possible result" variable.
If you are looking at the other tools, the problem is: they are all over that space, and you have no way to reliably find out where they are. Sure, it would be simple to use a tool which either has a very small gap between "best possible result" and "worst possible result" and as long as both are above zero, this would be OK for you. Or finding a tool which has a very low "effort to learn expertly" and an acceptable "best possible result". In both cases, you will save effort as compared to learning a whetstone. But simple is not easy: since you cannot recognize which tool fulfills these criteria, you are left with trying them out.
You can try to reduce the uncertainty by the usual way of searching reviews for a specific make and model. The problem here is that reviews usually don't recognize these three variables, but instead tend to give a single evaluation of the tool's performance, which is neither the best nor the worst possible end result, but the end result obtained with the reviewer's skill, and we cannot know what the reviewer's skill is. This makes their reported result a bad predictor for your future result if you buy the tool. Similarly, the price of the tool is also not a good predictor.
So, if you are OK with the uncertainty, you can buy a random (or, if you prefer, a well-reviewed) tool, try learning to use it, and if you are happy with it, stay with it. If you arrive at a point where the result is not satisfying for you, and you are either a) sure that the tool cannot do better, or b) you are not willing to invest more time in learning this tool, you switch to the next tool.
If certainty is more important to you, you can still go back to that whetstone, and invest the time needed to learn it until your knives come out sharper than you started. This is the same process as learning to do it perfectly, you will just experience success earlier, because you have more modest requirements.
What we can't do is to point to a specific sharpener tool and tell you "this will work well for you". First, I doubt that any of us has systematically researched different tools in all three dimensions to be able to tell where they fall on them, and second, even if somebody did, our site doesn't do specific brand/model recommendations. If you think reviews will be informative for you, you will have to look them up somewhere else, for example in test magazines or customer feedback in online stores.
Now to say a couple of words directly about things you stated in comments:
My impression was that for some knives, there is no option that does not require great skill but that for more everyday kitchen knives it is possible to get a reasonable result with something resembling one of the products I linked.
No, there is no such connection. Typically, if a tool gets a cheap dull knife slightly sharp, it will also get a good quality dull knife slightly sharp (again, with exceptions). It is just that "slightly sharp" tends to be unacceptable for people who buy the best knives, so they may express the opinion that it makes no sense to use these tools on their knives.
but then why are those products sold in supermarkets?
They are being sold because there are people who buy them, period. And all the ones get bought, both the good and the bad ones, because as explained before, as a buyer you cannot know which one is good and which ones is bad. When I said that these tools are all over the three-dimensional evaluation space, I meant it - some of them will always turn a dull knife into a duller knife, and no amount of practicing will change that. So, don't expect that just because there is a market for a tool (or even positive reviews) that it is good.