Microsoft does seem to be more of an exception though then the norm. I think Rayman is LONG OVERDUE for Smash. He should have been in FP #1. It is almost to the point where it is noticeable that he isn't in Smash. Characters like Bomberman, Crash, Rayman, Sora, and Spyro are almost head scratchers that they are not in Smash because they are such great fits, far better fits than some of the characters we have been getting in with the DLC.I've said it once and I've said it again, Sakurai and his team at this point really have no problem with putting Western Characters (Dark Samus, King. K Rool, Banjo, Steve) or Japanese ones that are mostly popular in the West (Little Mac, Ridley), their biggest bias may be that it's way easier to work with Japanese companies than with Western ones, especially during Covid.
Like let's take Minecraft's music for Smash. From what I've seen C4 had no idea about it, so it's not like he declined, but, they didn't want to contact - from what their point of view was, some, non-Japanese speaking guy who's currently living in Sweden as development of Steve was already hellish enough. If Minecraft was a Japanese creation they probably would take an effort to contact with the composer (like they did with Dragon Quest).
So Nintendo and Sakurai probably wanna work only with Western companies, with whom they have a great relationship like Microsoft (I'm counting Bethesda with them too) and Ubisoft.
When it comes to my favorite composers and those who make remixes for Smash, my dream team for Rayman's new arrangements would be ACE guys, Yoko Shimomura, Yuzo Koshiro, Masafumi Takada and Jun Senoue (although I know him might be the least likely as he only made one Mega Man remix and then yeeted lmao).
Hell I'd be cool if they would let Grant Kirkophe make an arrangement, as he already did one (which was meet with high acclaim) and considering Rayman's Western roots and how Grant worked on Mario + Rabbids soundtrack, I'd be a really cool thing to see, but it may be a pipe dream.
The FP seems to be more focused on JRPGs and if you see some of the responses from people on this board (Newcomer Speculation for example), it seems like most Smash fans, especially the younger ones, are perfectly fine with that. The original cast was heavily platformers (Mario, Kirby, DK) and even the original third-party DLC big characters were platformers (Sonic, Megaman, Pacman, to some degree even Snake). Yet we have moved away from that format to primarily RPG. We even see that with the Nintendo picks such as Byleth and Pyra. It has really sucked for people like me and my friends who want characters like Rayman in the game but I have gotten use to it. The only real DLC pick that created any hype for me was Banjo, the rest have been meh (I did kind of like Hero and Min Min).
I guess that I am setting myself up for disappointment. If you look, I was posting in this thread 2-3 years ago more excited about his changes but for each JRPG addition, it just puts more of a nail in the coffin. I do think that we will NOT get both Crash or Rayman unless there is another DLC pass (which I doubt will happen).