On the other hand:
Few countries use "college" to refer to "university" (most notably the US). In most countries, colleges either do not have degree-awarding powers, are merely high schools, or are part of universities.
In any case, when speaking to a global audience, "college" is ambiguous whereas "university" is less so.
Therefore, I suggest that university wins.
The underlying problem is that most questions originate in the US, where "college" and "university" have the same meaning.
The secondary problem (a very common one on SE sites) is the poor tag data:
possibly because "college" can be used in different ways in different countries.
But both tags are far too specific for the questions being asked.
When one is saving for or paying off one's educational expenses, does it really matter what specific kind of institution it is?
Perhaps both tags should be replaced by:
- education: Questions related to saving and paying for post-secondary education