Yup, pretty much. I’ve not worked extensively with Forestry, but I have with Netlify CMS, which is an alternative with a very similar premise. My experience was that it’s very difficult to build a robust CMS on top of markdown. If basic content editing is what you need, great! If, however, you need to accommodate a variety of conditions, things get dicey fast. The issue is that it’s exceedingly difficult to program or direct a CMS how to reason about even the most rudimentary primitive values or types in something as simple as markdown. After all, things are either there or they’re not. This can quickly causes your view layer to swell into an unmanageable mess.

Overall, I’d use it for personal projects if I were feeling fancy (I rarely do) or client projects with very simple requirements.

Forestry does a lot more than just abstract away the Git operations. It has a very advanced front matter template system that makes it possible to build very complex content models while providing a nice and simple UI for managing content, menus and media. It’s really quite impressive.

We’ve built a few sites on Forestry + Hugo and are very happy with the combination. https://www.jetflite.fi is a good example of a site having a rather complex content model.

It isn't just you, I tried and see my self staring at their blank pages for a few seconds and then everything appears at once.

"backed by git" doesn't mean the user has to interact with git at all. The user makes a change in the interface, the CMS creates a commit and pushes to the repo.