I like the idea, very ambitious I'm on a Mac so can't test but would love to.
My only quip with apps like this is file handoff, it'll require the next person to know how to understand the app in order to modify it. The difference between this and another app such as Animate CC from a user standpoint is that Animate CC already has a massive community of ex-Flashers that already know the app. Yeah, I know it's spits out clean code that "can" be edited but that wasn't the original format in was authored in (I'm assuming there's some sort of authoring file that this app works off of and it generates a different file -- but I could totally be wrong since I wasn't able to test it). This, unfortunately, is what I think what would stop something like this from catching on from the dev community.
What I think this would be a good component for, is creating modular blocks of code for GSAP hand-coders, or for when it's too much of a pain to try and hand-code something (i.e. character animation). Perhaps it can generate a block of code with a GSAP timeline that can be inserted into an existing GSAP timeline, or have an option to, some sort of process that makes that portion simpler. A way for non-coders to work with folks who code as well. More of a "component helper" to GSAP coders, rather than a full-on hand-coding animation replacement.
Perhaps it's a tool similar to Lottie/Bodymovin where it solves a specific niche.
Or, I believe you can include CSS/JS inside of the SVG format, maybe this app could include everything, including animation, in a self-encapsulated SVG file (I believe I was reading a thread or post somewhere from Chris Gannon (that super-talented SVG animator) who was trying something like this out. Oh yeah, found that link.
"Stop the madness!"-- lol.