Ask HN: Have you ever seen a pathfinding algorithm of this type?

Core … and a bit too vague. I'd be curious what happens to it if you run into a concave object. Image running into the back curve of a crescent, or, since diagonals are not legal moves,

       XXXXX
     XXX   X
           X
           X
 S - - >   X    E
           X
           X
     XXX   X
       XXXXX

Of course, the optimal path S → E avoids walking into that entirely.

Since it seems to be a game, though, the other consideration is "should the entity use optimal pathfinding?" Confounding an opponent with an odd shape could be just called "gameplay". (Different opponents might even have different levels of intelligence, and thus, different pathfinding. Some 2D games I have played have this exact mechanic.)

https://en.wikipedia.org/wiki/Visibility_graph

On a visibility graph you can run any search algorithm. The key thing is this graph is sparse (the number of nodes is really limited by the amount and complexity of the obstacles, not the distances).

This algorithm follows almost perfectly your outlined steps. In particular it draws a line to the destination, and if it encounters an obstacle it "walks" paths (generates successors for A*) along the exterior of an obstacle until it can "See" (draw a straight line to) the destination or another obstacle. By using "obstacle free distance to destination" as a heuristic at each node, this will provide optimal paths.

You can, just from the wikipedia page, deduce a good response to the problem of "select the optimal point for bypassing the obstacle". (Maybe try the vertices of the convex hull / AABB - and don't worry, it may take a few iterations to truly wrap around an obstacle)

This will perform much, much better on sparse environments than a grid, because a grid has to iterate O(n) for n grid cells, while a visibility graph has to iterate O(n) for n obstacles (of a given complexity).

Very nice!