One difference (among many) between AirBnB and my little project is that they have plenty of money to pay for automated translation where I don’t.
Does anyone have estimate about automated translation costs in their projects?
In any case, request a translation of a specific post to a specific language must be way cheaper than translating everything to all languages upfront, even when maybe you don’t get actual readers for many language-post combinations.
I don’t think financially it is such a big issue as you made it out to be, at least for some forums: to have a truly bilingual, automatically translated cozy little forum with about 500.000 new characters per month (about 250 pages, a whole book) would be completely free using the Google Translate API.
For 5 million characters (about 2500 book pages) you would pay about $100 per month.
I see many use cases for this: smaller forums without many posts, and large forums of companies/institutions who can afford it.