Andrew, not all rental income pays IVA in Mexico. The "Código Fiscal" specifies that only furnished rentals must pay IVA.
That being said, if you're on Airbnb you're most possibly renting furnished, so you should be paying: Hotel tax (in Mexico City, at least) + Income tax + IVA.
I totally agree with you on the fact that Airbnb is going about this the wrong (almost deceitful) way: IVA is a sales tax charged to the guest, usually 16% on top of the total nightly rate + fees charged to him/her.
The honest and fair way to approach this would be for Airbnb to automatically add IVA to ALL OF THEIR LISTINGS.
Otherwise, those of us who comply with the law, need to deduct IVA from our rental income or, alternatively, add it to the nightly rate and risk being the most expensive home in the area (and renting less = less income).
I'm hopeful that the tax authority forces Airbnb (and other platforms) to add IVA to all their listings and make this an even competition ground for all.
As of 2020, every listing must pay taxes in Mexico, no matter if the owner of the house is national or foreign.