I should preface this question that I am new to understanding the string landscape and swampland program and F-theory, so I apologize if my question is obvious / unclear!
Recently I was reading some of the literature of SO(10,2) M-Theory extensions, and F-Theory— specifically as “a toolbox” for studying Type2b non-perturbative effects, elliptic fibrations and axio-dilaton, etc. and it being a T-dual description of kk-compactified M-theory (less clear to me but I can grasp this); and came across a general introductory talk on the landscape and swampland by Vafa [https://workshops.ift.uam-csis.es/pgf18, “String Landscape and the Swampland” - Cumrun Vafa]. While all of this was a very trivial introduction (I assume to a more general audience than string researchers), there was one point of the talk I thought I would ask about.
About a half hour into the talk, Vafa references consistent theories without string theory description, and this can be “captured by some principle / motivated” by black hole physics in particular. My first question is, what are some of these consistent theories that do not exist in the string landscape? Where do they have a full description? How do we know, by a matter of principle, this is true? My second is, where is this black hole description of string landscapes further investigated? Is there an original paper / full survey of this relationship? Is this description even defined and known or is it speculated?
My last is more of a stupid question and not related to the talk, but it is not obvious to me. I am aware of the large landscapes of f-theory compactifications on CY4 (~10^272000 I have heard referenced) and those with standard model consistency (10^15), where are these estimates originally made and is there any case where F-theory is able to reduce the vast expanse of the landscape (say more like 10^500)? Are there other methods that are able to reduce the size of the landscape to less than that often cited 10^500?