The music industry loves Apple (NASDAQ: AAPL). Not only did the Mac maker help fend off rampant piracy by revolutionizing digital distribution, Apple has long been a champion of the industry's broader economics. Apple Music is now one of the largest paid music-streaming services in the world, second only to Spotify. The biggest strategic difference between the two services is that Spotify offers a free, ad-supported service, while Apple does not.

With Spotify recently filing for its forthcoming direct listing, public scrutiny over the music-streaming industry is only going to intensify. One Wall Street analyst now thinks that Apple should go the wrong way with music streaming.

Image source: Apple.

Should Apple Music have a free tier?

RBC Capital Markets analyst Amit Daryanani recently issued a research note (via Business Insider) arguing that Apple should offer a free, ad-supported tier for Apple Music as well. That notion "represents an untapped opportunity for Apple," in Daryanani's view. Not only would a free tier serve as a customer acquisition channel, but Apple could garner copious amounts of user data to fine tune its content-discovery algorithms. (Note that last year's acquisition of Shazam was very likely predicated on content discovery.)

Doing so could also help Apple's position internationally, where some users in emerging markets may not be able to afford the service. Spotify is growing fastest in Latin America and its rest of world segment. While the company does not disclose a specific breakdown of free and paid users in those markets, it's safe to say that monthly active user (MAU) growth is probably being driven by the free tier.

Data source: Spotify F-1. YOY = Year over year.

The good news for Spotify is that many of these free users do end up subscribing eventually. "Our Ad-Supported Service serves as a funnel, driving more than 60% of our total gross added Premium Subscribers since we began tracking this data in February 2014," Spotify states in its F-1 Registration Statement.

Still, this would be the wrong move for Apple.

Apple is terrible at advertising

Just about every time Apple has ventured into advertising businesses, it has failed to make a dent (remember iAd?). The company also fundamentally loathes compromising user privacy, which is a necessary evil of every ad-supported business. iAd was created specifically to help developers monetize their content and apps, not Apple.