Interesting, I've never before seen anyone claim that peak T directly influences hypertrophy, only indirectly by increased strength (in my opinion, this, if it occurs, would ostensibly occur by increased neural drive & nongenomic mechanisms).
A Fouad interview is entertainment, not data really. Whatever the doctor claims therein, transient changes to blood concentrations such as peak blood T would not logically alter AR number, within a muscle cell (which we know to be increased at supra-physiologic concentrations since Forbes' 1985 era dose/response data that failed to find a nonlinear portion to the curve plotting dose vs. muscle LBM & weight increases) and 1990s writings by Bill Roberts on the topic of AR up-regulation. Such a claim sort of reveals a facile, if not absence of, understanding of basic cell biology and androgens - or at least a poor application of one to the other.
There are 4 known mechanisms that regulate AR number: transcription rate (i.e., increased transcriptional AR mRNA synthesis), receptor turnover (i.e., decreased degradation-synthesis balance), translational efficiency (i.e., increased muscle protein synthesis per ribosome) & translational capacity (i.e., increased absolute muscle protein synthesis a la increased ribosomal biogenesis). We have since learned that there is no evidence of increased translational efficiency a la mTOR (i.e., no myogenic markers, nor markers of translational efficiency like rpS6 or p70S6K were altered by T in human skeletal muscle cells). But there is evidence of, at least, increased translational capacity by T (a la increased ribosomal biogenesis). Increased translational capacity is capable to explain, at least in part if not in toto, the increase to AR number by androgen/T.
Suffice it to say, all 4 of these mechanisms regulate intracellular processes, i.e., where androgen has already diffused through the sarcolemma into the cytoplasm where AR are located, and are not related to transient changes to blood/serum concentrations.
Tangentially, more to the point of androgen potentially increasing hypertrophy indirectly by increasing strength, I seem to recall Peter Bond mentioning something a bit obscure that I doubt he had thought too deeply about, that involved some data where muscle fibers exposed to androgen directly in culture showed an increase in specific force or something of that nature (going more to the idea that peak androgen/T might increase strength), but I think he'd walk back that association now and probably chalk it up to more likely rapid nongenomic mechanisms.