Ooh, careful with that question.... you really might not like the answer. In fact if someones low opinion is going to upset you, just stop reading now. :D
Generally I find them to universally be trash, often built by people not qualified to use the underlying language in the first place. Much like "frameworks" they have the illusion of simplicity, but that's all it is. It vanishes like a mirage the moment you try to do anything the generator wasn't designed specifically for, which in most cases is what anyone looking at it actually wants to do.
This is even more common when what they do is built around some rubbish client-side framework. Angular, react, vue, bootstrap, whatever -- they all reek in my experience of ignorance and ineptitude. Simply put, the people who made those systems simply do not understand enough HTML or CSS to be writing code that outputs, manipulates, or otherwise works with them. It's how people end up with two to ten times the HTML and 20 times or more the overall code even needed to do the job...
But then everyone touts how "wonderful" and "simple" having such massive impossible to debug bloat it? No.
Basically it has been my experience that when such tools try to lower the bar, they end up letting toddlers on the rollercoaster. That bar may actually have existed for a reason, to keep people safe. It has been my experience that "generators" be they simple front-end WYSIWYGs, "site generators", or for full stack development end up the equivalent of ripping that bar off the wall and clubbing the people duped into using them in the kneecaps.
Particularly given what such tools vomit up is a giant middle finger to usability and accessibility.
Which is why my day job freelancing involves going into projects for banks, public utilities, healthcare, and government agencies and ripping such things out of websites and applications with great passion and ferocity. Universally such places are utterly screwed over by such tools to the point it can even land them in court under laws like the UK's EQA and the US' ADA.
Now all that said, in a brief run-through of the website I could find no example of what Skaffolder produces as a end result -- but if it bears any resemblance to the laundry list of how not to write HTML that is the website itself? Yeah... just say no.
CSR only on what appears to be a static website? Static style in the markup? Static scripting in the markup? Zero logical document structure or scripting off fallbacks? Endless pointless presentational classes?
Hence the 2.3 megabytes in 51 files for the home page delivering 2k of plaintext and not even a half dozen actual content images. Almost like in addition to broken ignorant development practices it also let some artist under the delusion they are designer have their way with it as well. Laugh being it might even load faster if the whole site were a monolithic page with CSS/JS faking the appearance of multiple pages -- If it were coded properly.
Whoever built that site isn't qualified to build websites. Sorry if that sounds harsh, but that's the truth of it; or at least, not if you care in the slightest about usability, accessibility, search, maintainability, sustainability, or any other determining factor in proper site construction. A simple "view source" of Skaffolder's page should be enough to send anyone qualified to build a website running the other direction screaming in horror. Doesn't bode well for a tool aimed at people not qualified to build this stuff on their own... though entirely consistent with what I've come to expect the past six to seven years. It is a poster child for everything wrong with web development today.
Maybe if someone could make one of these systems that outputted semantic markup with separation of presentation (CSS) from content (HTML) that gracefully degraded scripting off, and didn't waste 20 times the code needed to do the job, I could get behind it. I've just never seen it done, nor do I even think it can be done. They're a cute toy for something like a blog for grandma, but anyone selling it to a business as something to use is -- and this is just my opinion -- a scam artist; because the result just sets them up for failure from the start.