I'm with you until you get to "and therefore marketing Christianity to a larger population."

This is 20th/21st century thinking. They had already been told to go out and make disciples of all nations. They weren't "eyeing larger populations" for marketing. They were deciding what was necessary for Gentiles. Since circumcision wasn't necessary (which was shown clearly by the fact that Gentiles had received the Holy Spirit without it (Acts 15:8), why make people go through it? The decision is presented as one primarily of compassion (15:19), not marketing.

Your "spin" is obviously possible, but I'd say neither necessary nor terribly accurate.

Perhaps we shall have to agree to disagree.

Alex