No, I don't think it is necessary at all.
Sure, Urology is competitive. If I recall correctly, this year's match rate is actually fairly in line with what it has been prior to 2019/2018; we've just had a few years recently with uncharacteristically high match rates. Didn't do any googling though to verify this at all.
You just need to do all the usual things to get into competitive residencies - good grades, good step scores (step 2 scores in your case I would think), research, extracurricular engagement to build an application, etc. Just like getting into med school. Certainly a research year doesn't hurt and if that's something you want to do for other reasons, like to build research skills for an academic career or improve your chances to get into a "top" urology residency, then sure, it helps! But I don't think it is necessary.
I personally don't feel research years are necessary for plastics, derm or ortho either. At least I feel that plenty of people in my class matched those without research years.