You can postulate such an object exists but you cannot realize it, so it doesn't translate to praxis. (e.g. you can't use the ultrafilter to decide an election)
That which can be constructed or described in a finite number of bits is more real than the phony numbers that Cantor justified. (e.g. Feigenbaum's constant is more real than any one of those real numbers that classical analysts try to bracket but never catch)
I got my honorable discharge from grad school and part of the climb in mathematical physics is reading some paper from 1957 that looked promising but after a close read you learn they got it wrong at page 47 and you have to figure it out yourself because you can't find the answers in the literature. You find out that the median scientific paper is wrong the hard way.
Wolfram wants to use computation (e.g. simulation, construction) as a praxis for all intellectual activity so he should privilege that map out of the Borges story over the territory of that deteriorating Empire which it mirrors.
Scientists in 2020 don't calculate in Cantor's phony numbers, but instead with those IEEE floats which never work quite right when you decimalize them.