It's very creative! LOL
But in practice most my tables that are uncapped end up with IDs are 64bits and i suspect not being the only one.. 32b is in fact quite small ~ 4B rows.
And so you would pay for the largest tier as it sounds like you have big data needs? ;P Whereas my company--which only had tens of millions of users and millions of dollars a year in revenue--certainly never had any tables with more than 4 billion rows... (not that I think this licensing model works or makes any sense at all, to be clear).