I believe she retold the story as Gaijin asking for an (at the time) top tier vehicle.
So she came up with two options, being the other two Ho-Ri designs (the ones that aren’t in game). Upon seeing that none were quite fit for the BR she made up a fictional “production” variant of the Ho-Ri as an option for Gaijin, similar to what Germany had gotten for their top tiers with the Panther II/Tiger 105. She also stated she told Gaijin about this before they made the final decision.
So while creating it was very much intentional, it was at Gaijins request for a top tier vehicle and with Gaijins full understanding that the vehicle wasn’t real.
But I’m not sure how accurate this is, it might be true, but it might also not…
I also don’t remember anything about that “japanese imperial family” stuff either, but I could of course always be wrong. Do you maybe have a link to that?
Anti-concrete or HE rather than SAP, It have equaly thick casting on all sides making it unfit for penetrating armour. Secound shows what usualy is reffered as SAP, but like “Granata Perforante 75/32” from Italian 75mm could be named APHE
Here from left: Granata Perforante 75/32 (APHECBC), 7.5cm Gr. Rot Pz. (APCBC-HE) and 75mm M61 (HE/APC-T). So different ammount of filler, all APHE
Yeah, I just went by what the technical manual stated. The base fuze can help with penetration though, and the shell walls are pretty thin, so it’s pretty likely it’s anti-concrete or mislabeled.
Nevertheless, I think the main round is going to be the HE round which is on par with most other guns in its caliber and that uses overpressure to frag vehicles.
Base fuse makes normal HE closer to HESH because shell explodes partialy burried/squash on target instead bursting in front of. This makes this shells better against Concrete and Steel armour, so we can suspect better penetration than standard 150mm HE.
Depending on BR placement APHE one can end as gimmick/secoundary round(like most of german WW2 HEAT)