To me this implies existence of a unique maximum representable value of float
float values are not totally ordered, NaN is not comparable with anything
In terms of partial orders both +inf and all NaN values would be considered maximal elements

Same thought is applicable to other floating-point types, and to minimum instead of maximum

I feel that a person that is not familiar with IEEE-754 could come to wrong conclusions regarding floating-point types

I don't think a deep elaboration is needed or necessary
A simple finite word addition could be sufficient, would match max() behaviour of std::numeric_limits