Like Aldo has flat out said and many other fighters, trainers included (Firas Zahabi for example), most are on gear. Especially the top guys/women in the sport in their respective divisions. Once they realize how much faster they can recover and how much harder they can train, they're hooked. That all translates into performance enhancement and for each sport the optimal "stack" of roids and PED's is different.
Jones also is not exempt from being a PED user himself, he could be for all anyone knows. Whistleblowers (even though he dropped no names) tend to be the guys doing it in the first place. Like that Jose Canseco baseball player guy that got hulk smashed in MMA by Hong Man Choi.
Problem is Aldo is, like everyone else, only speculating. When Congress started pulling in testimony from old teammates in the baseball PED scandel it sent the message: if you're using don't tell anyone. Don't tell other competitors, don't tell teammates, don't even tell your coaches.
The only people who know are the suppliers, and they're not talking. Which means the fighters, like everyone else, are just guessing about usage.