It's werid in a way that we are predicting the unpredictable. Like "yeah i see Crash as likely but im expecting Sakurai to bend over backwards and announce Peppino from Pizza Tower" kind of unexpected. Almost as if it was a rule.
I think this mindset started with Smash 4. The only expected characters that actually happened were Mega Man, Palutena, Pac-Man, Miis and Little Mac, (and Bowser Jr later though by that time few saw him as likely due to Rosalina's announcement). and the rest were curveballs. Robin, Lucina, Duck Hunt, the Koopalings as alts, Corrin, Cloud, Bayonetta (i remember when she was referred as a "hobo") and so on..
Ironically Smash Ultimate's base roster was pretty much easily agreed upon and almost all of them could be seen from miles away. Ridley? Already leaked by Vergeben, Jonneh and others. K.Rool? A lot of people expected him as soon as Ridley was announced. Simon? again, leaks, and Bomberman as an AT meant he had no competition. Isabelle, Chrom and Dark Samus? everybody noticed their absence in E3 demos. Ken? HAHAHAHAHAHAHAHA no Ken was confirmed as soon as Daisy was.
In fact, i think Daisy was the most unexpected choice for the base roster alongside Incineroar if you believed in the Grinch (Ken was so inevitable that he was going to be in even if the Grinch Leak was real) oh and Richter too. I know this may sound like revisionist history (there were a lot of Skeptics towards Ridley, plus back then people argued that Chrom and DS could suffer the same fate Isaac would ended up getting) but most of the base roster was very easy to figure out. The most unexpected were certain roster exclusions, namely a black hedgehog.
I guess that's why everybody wants unexpected characters nowadays. I mean the first 2 were Piranha Plant and Joker, and aside from Hero and Banjo and Terry (who only got talked about because of Nintendo doing an oopsie) most of them have been dark horses.