Edits such as this have received both accept and reject votes. What's our consensus on such edits?
Yes, but only when the information is not widely known or reasonably obvious to current-day users, and the explanation is not given by a question or answer on a StackExchange site.
One heuristic is whether or not we have a tag for the thing in question. If we have a tag for it, it's probably (but not always) well known enough that a link to an explanation isn't necessary.
Another is whether someone with a broad general knowledge of the era or area in question but not knowledge of that specific thing could develop an answer given that knowledge. There are a lot of questions I see here that I (and I suspect others) have no difficulty answering with a small amount of research; the correct links make that research faster and make it more likely that I'll do it to develop an answer.
What does a Nintendo Game Boy do when turned on without a game cartridge inserted? The Game Boy is so widely known amongst consumers even today that there's no need for link that explains what it is.
What happened to ZIP RAM? ZIP packaging for RAM is long obsolete and was used for only a relatively short time (late '80s and early '90s); most people who didn't use certain computers within that period would not be expected to know about it. Further, not all popular search engines give good results for "ZIP RAM"; though Google's first result is the wikipedia page, both Bing and DuckDuckGo have no relevant results on their first result page except for the question itself. This should have a link. (I'd like to see my proposed edit to add this restored, but it was rejected once so someone else who agrees with me should do that.)
What was the point of Apple Pascal having its own file system?, in particular the edit suggestion linked in the OP.
- A link should be added for "Apple's UCSD Pascal" because this particular product isn't widely known even amongst people who've heard of the computers that could run it. But it should be to the Apple Pascal Wikipedia page, since that it's a derivative of UCSD Pascal is somewhat clear from context, and very clear from the first paragraph of the page, which itself provides a further link.
- Links for "Apple II" and "Pascal" are unnecessary; even today most people know what these are.
- Links for "DOS 3.3" and "ProDOS" aren't necessary since all you need to know about those for the purposes of this question (that they are other Apple II DOSs) is already clear from context.
In a hypothetical question that mentions the Game Boy instruction set being different from the standard 8080 or Z80 instruction set, the "different instruction set" text should be linked to Is the Game Boy Sharp LR35902 object-compatible with the 8080/Z-80?. And it's perfectly reasonable to add a new question and answer to a StackExchange so you can link to it, if that question is appropriate for the StackExchange site. This would not be the case for something like "Apple's UCSD Pascal" in the example above, because "What is Apple's UCSD Pascal" is too general a question for an SE site, as explained below.
This differs from wizzwizz4's answer below because the RetroComputing SE is not an attempt to be a comprehensive archive of all information about retrocomputing, but is merely a set of (generally) narrowly-focused questions with specific answers. According to the help center, we should have "only...practical, answerable questions based on actual problems that [we] face" that are "reasonably scoped." As it says, "If you can imagine an entire book that answers your question, you’re asking too much," which is why we should link externally to general information and large, detailed resources.
Links to Wikipedia help to give extra context to posts, providing information about the topics mentioned that is far in excess of what can be provided in posts. This can help the understanding of the casual reader.
We already have tag wikis for providing extra information about topics - this question was tagged with apple-ii, file-system and apple-pascal at the time that the edit was suggested. Relying on links to external sites for information is frowned upon because this site should aim to be self-sufficient - that's one reason why we don't have link-only answers.
No, and when the information is not widely known or reasonably obvious to current-day users we should document that in a Q&A pair and link to that instead. (See Curt J. Sampson's answer for examples.)
- We're keeping all the necessary information on-site, not linking elsewhere for important information.
- It's fulfilling our mission to document and preserve information about retrocomputing for future readers.
- The Q&A pair could form a sort of thing index or thing hub, where an overview is given and further questions are linked for details.
- If they're not just giving a general overview, such questions could be too broad.
- There's a temptation to produce these Q&A pairs for things that aren't on-topic, such as alternating current or semiconductors. (Or is that just me?)