If you want to find out the meaning of a word, then check it out in a good dictionary.
In my dictionary, the word 'art' is generally synonymous with the word 'skill'.
Here are some variations of the meaning of the word 'art', as described in the Oxford English Dictionary.
1. Skill; its display or application.
2. Skill in doing anything as the result of knowledge and practice.
3. Human skill as an agent; human workmanship as opposed to Nature.
4. Skill in applying the principles of a special science; technical or professional skill.
5. The application of skill to subjects of taste, such as poetry, music, dancing, drama, oratory, literary composition, and so on.
6. The application of skill to the practice of imitation and design, painting, engraving, sculpture, architecture; the cultivation of these in its principles, practice and results; the skilful production in its visible forms.
7. Anything wherein skill may be attained or displayed.
8. A practical application of any science; a body or system of rules serving to facilitate the carrying out of certain principles.
9. A pursuit or occupation in which skill is directed towards the gratification of taste or production of what is beautiful.
10. An acquired faculty of any kind; a power of doing anything wherein skill is attainable by study and practice.
11. An artifice, contrivance, stratagem,wile, trick, cunning device.
I would say definitions # 5, # 6 and # 9 are particularly relevant to photography. In general, I would say this post is a work of art.