I have some questions about these claims (actual questions, not challenges):

1. there is nothing observed about this object that is inconsistent with a natural explanation

Along, perhaps. But in combination? Flat, highly-reflective, and subject to acceleration from solar radiation? What accounts for all these things and is still natural?

2. there is a large population of naturally occurring interstellar objects of a class consistent with ‘Oumuamua (about ~10²⁵ of them) expected to be out there

What objects are you referring to? Hydrogen icebergs, interstellar "dust bunnies," etc.?

3. and there is no better data forthcoming that can observationally discern between various explanations for ‘Oumuamua.

Loeb himself stressed this very thing many times in his book and (if I'm not mistaken) in the original study. The data gathered in the 11 days supports no conclusions, only speculation about a "new class of object." None of the "natural" explanations (he argues) fits what we saw.

His premise was that people should consider seriously (and always with skepticism) the possibility that it was artificial. Sagan himself said this about the possibility of aliens visiting Earth long ago.