Well that's what I meant, he's totally free to make an IGA style 2D game just as Inafune is making MN9, but Igarashi has even more freedom to get closer to our beloved IP because Konami can't copyright Dracula as a character.
But I can totally see him making something completely unrelated to Castlevania, because at least Konami is still wanting to do something with the series, when it came to Inafune, making MN9 was basically because Capcom threw the Rockman series into the dumpster.
And then set the dumpsters contents on fire.