Hi @test1234567!
While JSPs are still supported (as well as EcmaScript and JST) and it is totally possible to implement and use JSTL in this context I would not recommend to follow that path.
HTL is the preferred and recommended server-side templating system for HTML in AEM. AEM Core Components are implemented with HTL and they can be seen as a best practice reference implementation. Personally, JSTL feels a bit outdated to me in the context of AEM. I haven't seen it in a project for quite some time and can't think of any advantages that it would have nowadays.
Also I'm not quite sure about the approach that you are outlining. When you talk about "authoring JSTL tags" , you probably mean that in terms of the development cycle, right? Because I would definitely avoid to allow JSTL usage (as well as anything else that might somehow "smell" like programming including JavaScript and HTML source code) for content editors. That's a discouraged practice and comes with a whole lot of other implications to your applications stability and security.
Hope that helps!