You're either uninformed or splitting hairs about what "downranked" means. Google required AMP in order to be featured in the "Top Stories" carousel that was (unsurprisingly) at the top of the results page. Google ended this requirement in mid 2021, https://www.theregister.com/2021/06/28/google_amp_core_web_v...
Doesn't really matter. Google directed clicks to the AMP sites in various ways, including the OneBox. Most sites which need ad revenue had no choice but to adopt AMP.