BTW, it’s around 13.5 percent but regardless it’s not 80% (that’s a lie)

Sure, if you only measure after 6 weeks.

For women of reproductive age, losses between implantation and clinical recognition are approximately 10–25%. Loss from implantation to birth is approximately one third [39, 46, 48, 49].

A recent re-analysis [39] of data from three studies [46, 48, 49] concluded that, in normal healthy women, 10–40% is a plausible range for pre-implantation embryo loss and overall pregnancy loss from fertilisation to birth is approximately 40–60%.

https://pmc.ncbi.nlm.nih.gov/articles/PMC5443340/