I'm more on the side of "I can't imagine the size limit being much of an issue", with the notable exception Galaxiom pointed out about hardware (etc) capabilities.
After working in many projects on corporate data warehouses, it's a good reminder that - even though many people consider all their tables to be 'related' inside one specific project-based Access database, the same is not true for an entire business.
Out of thousands of databases and thousands of tables in each database where I currently work, it's helpful to point out that any given table may only be "truly related" to a handful of other tables. I'm thinking of a number of major customer data tables, there are only a few dozen that are hard related to each other in such a constraint-based way that they must be in the same db.
Most of the rest could be separated into different databases (and often are), and it would make no difference at all - any query can refer to any other database's tables on the same server.
Thus, while you may need to keep 10 or 30 tables in the same DB "because they are relational", that has nothing to do with another batch of 10 or 30 tables that 'are also relational', but not related to the first batch, and thus can easily be in a different database.
I wanted to point this out since although we often talk about all tables being relational, that's more applicable to the small, project- or theme-based Access databases that are a focus of AWF. Well, I mean, yes they're relational, but only to x-number of other tables at any given time.