I would have said reach-router, as it seems fairly well thought through, is constrained, and was originally an attempt to correct deficiencies in react-router. But it's being merged into the next version of RR.
What anm89 says is on point. All solutions available are awful in their own special ways. If a router solution _is_ needed, and there's no chance you can't just rely on the browser history API, imo stick with RR despite it's major downsides, because at least there is the major benefit of vast community support; all solutions seem fairly shit otherwise (just cross your fingers you don't need to do any React Native work that needs a routing/navigation library cos hoo boy it's a shitshow)
What anm89 says is on point. All solutions available are awful in their own special ways. If a router solution _is_ needed, and there's no chance you can't just rely on the browser history API, imo stick with RR despite it's major downsides, because at least there is the major benefit of vast community support; all solutions seem fairly shit otherwise (just cross your fingers you don't need to do any React Native work that needs a routing/navigation library cos hoo boy it's a shitshow)