My feeling about GitHub Pages is that it is not unreasonable just to forget about the site. For any cheap shared hosting I would psychologically feel the need to monitor the site somehow, periodically check that the credit card works etc.

For me, there is a large relative (percentual) difference in the perceived cognitive load. Perhaps not a huge actual difference, but when you are running tens of projects, everything counts.

Now I am not talking about actual reality but the psychological effect. It might be that some shared hosting site is in fact more reliable than GitHub Pages.

Obviously, a blog that you just forget is not that useful, but last site I created using this method was an advertisement site for a book. I have several blogs where I write occasionally.