The RT hardware takes up a small fraction of die area based on some articles I read a year ago. Furthermore, RT isn’t a gimmick: it’s literally the holy grail of graphics. Ask yourself why AMD, Intel, and consoles are all moving to it this year.
I don’t doubt it will be fantastic once it’s actually usable in the sense that people will choose to enable it. I fear next gen consoles, like current top end PCs, will have settings where you choose 4K/60fps/raytracing and you can enable two of them, or possibly just one. In priority order, raytracing is a distant third of those.
I think they are all moving to it because they know they need to get there eventually, and they need consumers to pay for it all the way.