Posts about things that go wrong are very common. Posts about things working like they should don't usually happen - why would they? It's working just like it's supposed to be. So, for every post you read about something going wrong, there are that much more experiences of those things going right.
Also, there are plenty of discussions about leaks in other RVs - they just aren't happening in the cabover.
So, while a C is more likely to have a leak in the cabover (funny, it's the only RV, other than a TC, to have a cabover, so that makes sense), it's not necessarily more likely to leak than another RV. I had more problems with leaks in my TT than I do in my C - both were corrected easily by taking the time to properly seal the seams, etc.
Same with a slide. Of course RVs with a slide are more prone to have slide problems - they are the only RVs with slides. But are those problems really so common that having a slide isn't advisable? Probably not.
In the end, if another type of RV better fits your RVing-style, then sure, eliminate the risks of a cabover leak or slide problem by not having either. But if a C and/or a slide best suits your RVing-style, then the potential risks are most likely worth taking.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)