It's a gimmick. Very few games have convincing effects and the impact on performance is still high. It's worth remembering that this has been pushed to players since 2018, even though the hardware wasn't ready yet.
Obviously Cerny is putting his faith in this, because he is already thinking about the PS6 and there, RT performance will be increased and become an industry standard.
We are in a transitional period, so obviously, it is not 100% worth it. It's like the transition from 2D to 3D, the PS1/Saturn games were very rudimentary. Vast games with satisfying 3D, only from the PS2 generation onwards.