The point is MS didn't have that 'many' more exclusives even on the 360, which people seem to look over, even the 360 didn't have IP like Yakuza, Persona, Dragon Quest Ect. Despite MS spending millions on Mistwalker and working with various other Japanese studios it all made little difference in Japan The 360 was still totally outclassed in Japan and it's not like the Mistwalker games sold 'that' well and most couldn't even give a toss about FromSoftware exclusive support on the 360 with Ninja Blade, Chrounds or Enchanted Arms all selling well below a million. You really can't blame MS for thinking Japan was and is a lost cause...
Many liked the 360 because of 3rd party games in the main or MS IP like HALO, Forza, and Gears which the XBox One has its self. Many of the issues the XBox One got in terms of lack of In-House IP or major Japanese exclusives were already there on the 360 and why I had issues with the way Robbie Bach and that total tosser Kudo Tsunoda were talking MS and the 360; With that waste of space Kinect and $500 MILLION of MS cash that should have been put towards proper games, not Kinect and mum and dad trying to dance in front of the TV.
The main difference between the One and the 360. Was that the 360 was the best selling console in the USA the 360 as the choice system to lead development on and winning out for most Digital Foundry compassions. When it came to Japanese support and In-House exclusives I thought SONY owned MS and the 360, Actually think the PS3 was the better system, but that's just me
Actually the Wii outsold the Xbox 360 in the US.
Also, to your point about 360-era Xbox exclusives, at the start of last gen. MS enjoyed a metric crap ton of essentially "de facto" exclusives, due the difficulty of programming for the Cell causing a lot of devs and publishers to simply forgo PS3 development.
Not only that, the 360 released a whole year ahead of the PS3 too, so pretty much every third party title releasing in that year was effectively exclusive to the Xbox.
I think a lot of that contributes to the perception that the Xbox 360 enjoyed a lot better exclusive software support than the XB1 (which is still essentially true for the most part).
MS was taking more risks during the 360-era too and funding more games, like Blue Dragon, Lost Odyssey, Mass Effect etc..
This gen, the XB1's initial poor performance combined with the latter-gen PS3 success Sony enjoyed, meant that less third parties would be willing to forgo the Playstation audience and sign exclusive games for the Xbox One; especially with significantly higher development and publishing budgets this gen.
All last gen, MS should have been fostering close exclusive development relationships with third party developers (small and large) as well as building up their internal studio roster. They actually did invest in the former with devs like Remedy and smaller devs like "The Maw" devs, but when Kinect hit it big they seemed to abandon that strategy and go all in chasing the casual gamer.
Now they're paying for it, since it's a much more expensive game to try building up third party exclusive dev relationships and first party dev studios this gen. The financial risks are much higher now with developing new IP, even with seasoned talented existing studios. Trying to do that with newly formed studios with little experience and without any tried and tested studio game engine codebase/tools, the risks might end up being much too great for MS to gamble on, especially considering their current market position. Even trying to leverage old back-catalog IP with a newly formed studio can be a huge gamble... one that has the potential to bring both financial failure as well as damage to the IP itself... just look at EA with ME:A.
