Considered outdated by whom though? Turn based games were fine, the companies making them were doing a poor job at innovation during the PS3 era. They fell into a creative rut and kept redoing the same thing over and over. FFXIII actually had some interesting turn based mechanics but the story and level design were what sunk the game in the eyes of many of the fans.
I suppose it was the critics of the time, and they genuinely had the ability to tank a game with poor publicity during that era. These days we know better.
It was during that time that Keiji Inafune said that Japanese game development was way behind the west, seemingly because he loved western game design, leading to outsourcing many capcom properties to western companies, also the head of bioware and the lead designer on fez also dunked on Japanese game design, especially turn based games.
Seemed there was an anti-asian/xenophobic aspect to it, I looked it up not too long ago and it genuinely just seemed "asian game = bad" as far as western game developers and journalists were concerned. This was during the age of anything that wasn't brown/grey with guns didn't do well. PS3/360 Era.
As for whom considered it outdated? you have a point, I didn't, no one I knew considered it outdated either. I'm now just thinking it was a narrative in a journalist echo chamber that thought everything western RPG king Bioware made was gold, now bioware is a joke and square and atlus hang their heads high.
The "hate" for turn based games showed up around that time as many of the best selling games before this, on two console generations, were turn based and genuinely it was just blanketly referred to as archaic asian game design and turn based RPG's were a staple of it.
Even the term JRPG is used to almost differentiate these games for some reason and make it seem lesser to some. It's just an RPG from the east.
I loved FF13, especially lightning returns, and the story and characters don't get much fleshed out in that first game but I still have soft spot for it.