Yes and yes.Is the concern that they will eat the small shrimp fry or they will eat the adult shrimp?
You're seeing reports of them eating shrimp because they will eat shrimp. And if they can't choke down a fully grown adult? They can maim, harm, harass, kill them - and then consume the pieces. When it comes to fish like this? When some people share one experience and some other people share a different experience, it's because both experiences are possible. There's no one, true answer because there are way too many variables to consider. Some of those variables: the individual specimens, tank size, aquascape, line of site, feeding habits, hiding spaces, et al.
It has been resolved, fortunately. Like @klibs says, if it can fit in the mouth of a fish? It can become a snack. That goes for all fish - even fish smaller than shrimp.it hasn't really been resolved
But you hit the nail on the head about varying circumstances and working to have a healthy population.
Shrimp like Neocaridina and Caridina (especially Caridina) are cool water species and do best in cooler temperatures.The shrimp want a more tropical tank.