On those web projects, is Git used just for versioning the delivered assets (psd, jpg, and gifs) or is it used for the working files (Illustrator, Photoshop, etc)? I've used it for the former, which is why I said it was more manageable, but not a great solution. If you were to treat it like we do code, you'd only commit the working files and have a build script to generate the deliverables.
Those are tooling problems, but I also think there are architectural problems. I don't have a lot of experience, but I have looked at git-lfs. You need a separate repo and also a separate path for data, right? It's also an add-on. It's all working around Git itself. For artists, what's the value add over Perforce or SVN? I can see that maybe you could use the same tools as the coders, but you have a bunch of new problems. I'm not saying it doens't have its place. I can see myself using it in the future, it just doesn't look like an out of the box solution.
A few years ago I was toying with something that would be more like how a lot of backup systems work (and I think macOS attempted something like this a few years ago and abandoned it). Each time you save it will make an auto-commit, if your app has integration, it takes a screen shot and stores any metadata from the scene (this was targeting a 3d application, but with the goal of also working with the filesystem directly). You could also make an explicit commit and give a commit message. Auto-commits would get flattened into hourly, daily, weekly. Explicit commits would stay around as indefinitely as you'd want. Git was a poor backend for this because I don't think you can merge commits in the background, that also rewrites history. This was focusing on version control for an individual, ignoring collaboration and merging.
The whole reason Git was written is because the data-structures facilitate the needs of the Linux kernel's programmers more cleanly (“Bad programmers worry about the code. Good programmers worry about data structures and their relationships.”) I feel like a lot of these Git tools for artists are coercing Git's data structures into an awkward workflow. That's the biggest reason why I hope it's no the end of the road for VCS.
Thanks for introducing me to Abstract. I know I've seen similar attempts in the past. I hope it's useful to artists and I hope Abstract is a successful business, but I'm a bit bummed that Open Source is relegated to a sub-group of programming.