In this case, good for the developer is good for the user. As users, we get 1) tons more of those (since they’re easier to build, with one codebase that runs on literally every modern computing device, from phones to tables to laptops) 2) without being locked into a walled garden 3) fairly securely (heavily sandboxed, unlike desktop apps).

The sheer number of cool things that got posted on HN in recent years leveraging these APIs.