Well, since this place is open again...
I mostly agree with Sable. I find it unlikely Klonoa will ever get a new game. It's not like Megaman, where Capcom decides to flip the bird to a large and dedicated fanbase on a yearly basis. The last Megaman game is only 4~5 years old, the fanbase was always large, and he got included in Sm4sh which is going to boost his already formidable popularity through the roof. No, Klonoa's last game was a disaster, was a dozen years ago and Klonoa has sadly never been that popular. Klonoa had a rough start to begin with. His 2D games came out in a time where 3D platformers were taking over the market. And as the years went by, gamers were more and more interested in gritty, realistic games, the opposite of what Klonoa is. There was no hope for him then, and it quickly went downhill from there.
However, there is a silver lining. 2D platformers made a comeback. The indie scene is strong, and games like Klonoa's are now very much on the forefront of the industry. If Klonoa was to make a come back, now would be his best bet.