One thing that really hurt the global market was the same factories that cranked out the raws needed for AAS also produced Fentanyl. So the overlap just shut everything down. I think this was around 2022 when it started to get bad. For example: I could get super clean 200mg/ml Primo for 60 USD. Now, that's non-existent.
China has a weird, almost unbelievable thing they can do. If X is missing from the market, they will build a city and facilities to make it. For example during the high of COVID, they erected a full hospital in a few days. The US or EU could never do that.
Edit: Again I am trying to translate your response to English. If I make a mistake, please correct me and I appologize in advance.
Edit: Changed Fent to Fentanyl in the first paragraph.