FWIW I’m seeing people conflating Jamstack and headless CMS (eg Contentful) a lot lately. The latter provides an infinitely better editing experience for non-tech users. But the non-free tier can start as high as $500 / mo (the amount of shit you could tack on a WP site for that money...) and as one of the top commenters has said I think that even for a best-in-class headless CMS, the non-techie UX starts crumbling as soon as you start adding typical features outside of content editing (forms, analytics, etc)