That's not in the press release. Pretty sure that was Guff's summarize/educated guess.
https://pressroom.toyota.com/toyota-gr-supra-adds-manual-transmission-and-enhanced-drive-dynamics-for-2023/
A while back Toyota said their own survey had found that around 30% of buyers would opt for a manual trans. I forgot who, but one of our members here who attended the Toyota dealer meeting said the breakdown for the 2023 model year would be 40% manual and 60% auto.
A press release means that it has been officially confirmed and is no longer a part of the online rumor mill. For the 86 it was done in stages. It's not uncommon, tons of auto markers lunch new products through a similar process.
Official announcement...