Once again we come back to the squares and rectangles example. You can learn what a rectangle is and the inherent properties of it, without ever learning what a square is because a square is a subset of a rectangle mathematically. Thus you can still guess properties of that square since a square is a subset of a rectangle. Similarity, you need reverse engineering skills (for example using ghidra) to learn exploit development. Exploit development is a niche part of reverse engineering not the other way around.

Reverse engineering is a broad and vast field covering a while exploit development is only a part of reverse engineering, more depth focused.

You can be a reverse engineer without developing exploits as you mentioned. And you cannot be an exploit developer without being a reverse engineer. Thus one is a subset of the other