Pixelmator somewhat fits that (minus the half-assed part). Pixelmator is, at least for now, pay once. And given Apple's size I don't see them trying to squeeze customers for Pixelmator subscriptions. It definitely isn't a full vector program at the level of Illustrator/Affinity. But for a lot of people it probably has powerful enough vector editing.

I see that there is Pixelmator ($50) and Photomator ($120), both from Apple.

Any idea what the difference is? The cheaper one looks more capable.

Pixelmator = Photoshop

Photomator = Lightroom, but without the library management