PRP is widely available now. Sometimes branded under the trade name Priapus Shot or P-Shot. It just hasn't delivered consistent penis enlargement so it doesn't attract much attention.
Now they're promoting PRP as a possible ED treatment that might work in 24 hours, or maybe after 3 more treatments, or maybe after 4 months. Or it might be promoted to rejuvenate the penis, promote healing, or to restore blood flow.