I would like to know what "ought to make a good thing out of this" means in the following passage:
His utterance of the name ‘Mr Fadge’ sufficiently intimated that he had some cause of personal discontent with the editor of The Study.
‘The author,’ remarked Milvain, ‘ought to make a good thing out of this.’
‘Will, no doubt. Ought to write at once to the papers, calling attention to this sample of critical impartiality. Ha! ha!’
Jasper Milvain, the protagonist of this novel, was invited to Yule's house and met the literary critic Alfred Yule. Then Jasper asked him whether he had seen that the literary magazine The Study of this week contained a very pleasant review about a novel named On the Boards which was seriously abused some weeks ago at the very same magazine. At this, Alfred Yule expressed undisguised pleasure at The Study's mistake, and the corresponding misfortune on Mr. Fadge, the editor of The Study. And Jasper commented that the author of On the Boards "ought to make a good thing out of this."
In this part, I would like to know what "ought to" and "make a good thing out of" mean. Does it mean that the author would surely raise an opposition against the two reviews diametrically opposed?