I dislike the idea of these separate tools being blended like this. ty is currently perfectly usable on non-uv projects. uv has *a lot* of opinionated quirks, its custom lockfile lockfile, and other nuances which many of us dislike — ty being a separate tool works fine with plain pip plus any other dependency manager (e.g.: pip-tools).
Of note though, ty doesn't NEED to be integrated into uv, nor vice-versa; keeping them as standalone tools seems most natural.
Projects that use ty for its type checking but something else than uv for managing dependencies are probably in a very tiny minority of users.
Thank god it has opinionated quirks that old timers dislike.
Otherwise we'd still be stuck in the complete dumpster fire that was the python packaging/venv we had for the previous 20 years.
A implies B does not mean B implies A too. You can use ty separately, this isn't stopping that, but it is useful for uv check to use ty together.