this is a method, and always was a method, I just wanted it to look like an attribute for aesthetic reasons

I think "aesthetic reasons" is an oversimplification. There are certain assumptions a developer makes when reading some code that uses properties. While these assumptions are not clearly defined and may differ per developer, I think there is a common core.

(1) There are no side-effects. The object is not mutated (or any other object), no IO takes place.

(2) The time and space complexity is O(1).

(3) The result is consistent. Consequent calls to the property should return the same value unless there is a mutation between them.