A future for SQL on the web

Using native UI frameworks will almost always yield smaller file sizes than the equivalent implementation in any of the web technologies, regardless of whether served as a webpage, or bundled in a WebView or something similar (with few exceptions, one of which is listed below). Just consider a WinForms/GTK/Qt or a similar application in contrast to using React/Angular/Vue and including those within Electron, or even loading them in a web browser.

Many of the mobile applications out there actually include hybrid technologies (like Ionic, React Native, Xamarin or anything else of the sort), since nowadays telling a company that you'll have separate codebases with OS native widgets for iOS, Android and others would not be met positively. Therefore, concessions are made to speed up development, at the expense of having more abstraction layers and larger bundles.

One aspect in which you're probably correct, however, is that technically the web indeed affords you the possibility of having pretty good download space savings, if you choose which forms to make user download, as opposed to including all of them in the application. For example, if you have a billing form that actually needs 50 different variations based on countries and regions, and include them bundled into a native app, then on the web you'll instead be able to just download the one that you need dynamically. That said, none of this is alway easy, hence Twitter and Uber both employ a large number of engineers that work on screens like that, even if many people won't even see them.

My point here is that there are many different approaches and technologies that can be used, "native" in the context of my message meaning an application that uses the OS UI and widgets directly, without reinventing the wheel or attempting to encapsulate cross platform or web technologies within it. Of course, it's perfectly understandable and valid why companies that are highly focused on their own brands and shipping quickly don't necessarily adopt that approach.

I'd like to add one drawback with this solution: Complexity.

From my experience, complexity can easily lead to more problems than what it solves. With all the "blackboxes", e.g., WASM, JS, SQLite, IndexDB, ..., it might be hard to find bugs. Most of the tools used are somewhat stable and mature tough. SQLite, for example, has a whooping 100% test coverage (line coverage at least).