I think that when possible, we should strive to make questions as generally-applicable as possible. I don't think we should allow for questions to vary only in which engine the asker happens to be using, with some caveats:
- If a question is only making reference to some tool or engine to indicate that's what the user is asking, and the topic of the question is not a task specific to that engine, I think we should try to generalize the question where possible.
For example, the process of cooking or compiling data to runtime-ready formats is not something every engine does, and something every engine does fairly differently. So a question about fixing some behavior observed while cooking assets in Unreal is a reasonable Unreal-specific question, and shouldn't be generalized away. However, the task of creating a pizza-cheese-like graphical effect is not generally something that is engine-specific itself, and should be generalized.
This doesn't preclude answers being technology specific (and to that extent, I'd say that the process of generalizing a question should be to remove tags, but not necessarily to excise all references to the specific tool/engine in the body text). This way, we establish a pattern of a canonical, agnostic form of question and an associated set of answers, some of which may deal with the specific processes of accomplishing the task in a specific engine, versus just describing a general overview. This creates good duplication targets, it creates good, all-in-one-place threads for search engines to index, and it provides a compelling benefit for users to post new answers addressing the problem in other specific tools, if so desired. How can I trigger code once is a great example of that sort of question.
Conversely, though, we shouldn't be overzealous in generalizing questions:
- If the specific text of a question reveals the problem is really related to bugfixing/tweaking some problem specific to the implementation of the general task in some specific tool, we shouldn't attempt to generalize that away.
For example if the question in the original post were asking something more specific, such as "what knob do I need to twiddle to make the afterimage sprites fade out over time," that's not something I think we can turn into a general question, so this isn't a blanket rule.
If the user doesn't know how to perform the task at all, the question is probably suitable to be made as general as possible (although answers can be tool-specific). If user does know how to do the task, but is having a specific problem with it (possibly as relates to a specific tool/engine), it probably shouldn't be generalized.
In the long run I think more general, canonical questions are better for the health of the site.