Was recently noting a console war thread on a PS4 centered channel (which I monitor on Youtube so I can get some other perspectives), and noted a bit on console exclusive infighting between the consoles. 

A lot of things came up, but Yoshi and Kirby were notably absent. Even during Exclusive versus Exclusive beat downs, they were not thrown out despite their confirmed 2018 status. 

Is it just because they are pretty good for kids? Or is there another reason. 

The PS4 really doesn't have any good corollary for Yoshi and Kirby.

Yes, it's because they're designed for children and casuals. Good games but easier to beat than a handicapped child in a wheel chair.

They just aren't system sellers as compared to Zelda or Mario

They usually sell just fine though

Its not like ps has any comparable exclusives.
Besides switch has the end all be all card that ps doesn't have in pokemon anyway.

It's because they aren't system sellers. Although personally I'm excited for both, I don't think they're a good argument to bring up against something like Days Gone, God of War, Detroit, etc.

Also ... you didn't even mention Mario Tennis so ... who's more unnoticed now? xD

I don't know about Yoshi, might get it but Kirby is a day 1 buy for me. It's just a solid, great looking Kirby game. I think it'll go on to be the best selling Kirby game of all time, but yeah overall these games are not games that bring in huge amounts of consumers. But, in building an install base you need games like this to continue to build the install base. It's like an "Every penny counts" type of thing.

If the challenge is finding a challenge within a game, said game is not challenging.

They're B Tier, plain and simple.

Not just that.

Kirby sells way more than Xenoblade games.  But Xenoblade games are so high quality and hugely ambitious games that they are taken way more seriously.

Kirby and Yoshi games are good, but nothing like epic or games changer. They aren't at the highest level.