I downvoted it because only a couple of small modular reactors have been constructed so far, and neither of them use spent fuel rods from older reactors as fuel:

https://en.wikipedia.org/wiki/HTR-PM

https://en.wikipedia.org/wiki/Akademik_Lomonosov

If you were referring to a theoretical SMR design, I will believe it after a demonstration unit is built and operating. Most reactor designs never enter industrial use, just like most designs for new kinds of batteries or solar cells.