If you use it to just get started, but actually read it and have the expertise to fix mistakes and make it relevant, it's probably fine. Not necessarily because it's faster, but because some people just suck at getting started, and having nonsense to correct is easier to start correcting than turning whitespace into something.
Its just an intro. Who cares if its shit? Just need words there that sound like the author wrote them because its expected in case someone accidentally reads it instead of skipping it as usual.
There'll always be someone new to the field who does actually have to read the intro. I read a stuff outside of my field all the time and I rely on the intro to not have to go find a review just to broadly understand a given paper.
Can't say the intro has ever been particularly useful, even if new to the field. If the methods aren't detailed enough to understand the methods, then you are going to have to look elsewhere. The intro isn't going to have that information. If you want a general summary of the field, a dedicated review is far far better than most scientists trying to fill space to get to the science.
When a paper is far enough outside of my field I'm not going to be knowledgeable enough to critique methods. I'm not "new to the field" in the sense that I'm starting research in that area. Just thought the title was interesting/cool and I want to know a little bit more about the specifics. I don't actually care about the field enough to study it (if I did I'd look for a review). So I'm not trying to understand the field but the just the paper(broadly). Why is the thing they study important? How did they (supposedly) come to their hypothesis? Just how badly is a news report overreaching what the source states? Etc.
Yeah, fair enough. Someone here in the thread already said they use LLMs to just outline what to write and how, and then start something along these lines from scratch