He mentions that studios assumed people copied rented tapes, but I have to imagine that was relatively uncommon. Not many people had two VCRs, and by the time VCRs got cheap enough that people started to have multiples, most rental VHS tapes were protected by MacroVision[0] copy protection. Which was relatively easy to bypass if you knew what you were doing but wasn’t something the average home movie viewer was going to bother with.
[0] https://en.m.wikipedia.org/wiki/Analog_Protection_System