I don't know how to formulate this question -- let me try the following:
Is it really meaningful to ask how large the Universe is?
or
Is the Universe finite in size?
or
Is the number of stars (and hence presumably planets and presumably
civilizations) countably finite?
and
BTW can I say that the number of integers is "countable" and still mean
infinite?
Can I say that something is "countable" and restrict my meaning to "finite"?