I am an intervals.icu user as well (what a fantastic program, btw), and was noticing that my training is falling mostly in the pyramidal category. So I had these same questions.
There is quite a bit of reading to do on this in google scholar. 
That’s why we “hire” Coach Chad, and Dylan Johnson. I have yet to dig through them all, but the top one listed seems positive about pyramidal training, at least wrt to half-ironman training in recreational athletes:
If I had to venture a guess, I would say that traditional base sounds better if you have 10-14 hrs a week. SSBHV does seem excessive, but maybe it matches certain cycling goals or rider types better than others. I would also guess that low and mid volume SS plans make more sense for the time-crunched athlete.