Some people seem to think that having characters from other, more popular franchises (like Akuma in T7, or horror movie icons in Mortal Kombat games) is extremely desperate, but what's your opinion on this matter?

I do believe it's very sad and desperate, but when you're at a point when your franchise no longer generate buzz, gets nothing but bad press, and nobody seems to be interested for your upcoming mainline title, there is really no other options (like Akuma from the 2016 hit fighting game SFV joining T7).

Trying again after the first thread was instantly closed is more desperate.

Its definitely very cringeworthy to me. Its like certain games can not be successful on their own without piggybacking the merits of other actually iconic framchises.

Lets not forget soul calibur jumping the shark by including star wars characters. And i am appalled to see tekken 7 resorting to giving Akuma a roster feature

Definitely. Tekken 7 really needed that feature but it probably won't work out anyway!