Honestly, Joystick doesn't seem at all like React, Vue, or Svelte. You have a lot there in terms of email templates, database connections, and other "full stack" items that far exceed the scope of the others.
React is certainly a LOT more cognitive overhead than plain old HTML/CSS/JS. Vue, yes, to a lesser extent than React. But honestly, Svelte is closer to "just plain CSS and HTML" as I've even seen in a framework that also allows two-way data binding, which let's face it is a RPITA in vanilla JS. Automatic scoping of CSS to a component is also nice when you aren't trying to set a global style.
This by the way is coming from a guy who started writing for the web in 1996, back when document.write() was de rigueur. That said, I honestly do miss the old days of figuring out how to make something on a web page by simply hitting "View Source" and picking out the relevant tags.