The measures were put in place to prevent building owners from turning their apartment complexes into unregulated hotels to avoid paying additional taxes. Because those hotels were unregulated anyway, they often were in a lax state, and so health and safety also became an issue.
Conversely, per Airbnb's quote, 87% of the rooms listed on the site are people's own homes of which they rent out a portion, or the whole thing for a limited time they rent out. So these are not people trying to circumvent the tax law (and by all means tax their Airbnb income as a hotel would be), they are just trying to make additional income to live in one of the most expensive cities in the world. Those 87% were not the target of the law, because this model did not exist at the time.
Conversely, per Airbnb's quote, 87% of the rooms listed on the site are people's own homes of which they rent out a portion, or the whole thing for a limited time they rent out. So these are not people trying to circumvent the tax law (and by all means tax their Airbnb income as a hotel would be), they are just trying to make additional income to live in one of the most expensive cities in the world. Those 87% were not the target of the law, because this model did not exist at the time.