This question as an example
There is no doubt it is a buying recommendation and violate the rules.
However, on an engineering stand point, this type of question does make sense and would be useful to many.
It is true that there are no "absolute right answer", however it is still a very useful information.
The technicality doesn't differ much about a question on circuit design as often there also isn't absolute true answer and many approach can be taken and is open to personal preferences.
Here is an equivalent question on stackoverflow which isn't marked as off-topic.