It’s definitely tested and proven, that’s a very common approach (not this specific migrate tool, but the general pattern). It’s simple to setup and only require standard SQL (or whatever your DB is using), has almost no moving parts, and is as stable as it can be.

I’m not saying it’s easier than other solutions, that’s not really a criteria I personally care about. But it is stable, simple, relatively easy to maintain, using standard tools, reliable.