When it comes to third-parties and Pokemon characters? Sure. Otherwise Sakurai has the final say on Nintendo characters. As shown
here and
here
None of those characters are promotional characters. Daisy has nothing to promote that isn't covered by Mario himself and he sure isn't a promotional character. Same deal with Ridley since Samus alone is already enough to "promote" her entire franchise so in that regard, Ridley serves no advertisement purposes.
And just like the Inklings, he isn't even based off the latest game in his franchise with Samus Returns and Splatoon 2 barely having any content in Ultimate. How are you supposed to promote upcoming games if you don't even try to use Smash to represent and remind players that those games exists?
The only characters that ever got in order to promote an upcoming are
![Corrin :ultcorrin: :ultcorrin:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
and
![Roy :ultroy: :ultroy:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
(and the latter only got considered because he was a feasible last-minute addition, so promoting an upcoming game wasn't even a priority for Melee).