Yikes. For those who do not see a difference in what OTs and RTs do, I highly recommend you complete more (or start, if you haven't yet already) observation hours to get a better understanding of what OT is about or find a better facility/mentor to observe. They are not at all alike.
It may look alike at moments from a superficial stand point. Here's an example.
An RT engages a TBI patient (who previously enjoyed playing cards) in a game of go fish so that they can assist with their return to meaningful hobbies.
An OT may engage the same patient in a game of go fish. Yes, because it was a previously meaningful leisure activity. However, our focus (and documentation) will reflect things like: cognition (memory, sequencing of multiple steps, initiation of activity, problem solving), visual perceptual skills (are they scanning the entire field, do they have neglect, do they have issues with figure ground, depth perception, etc), fine motor skills (are they able to hold their cards, do they use both hands or is one side weak), gross motor skills of upper extremity and/or trunk (can they reach across/to the right/left to reach the cards or is the motion limited at elbow/ shoulder? Do they have enough balance and core/back strength to even sit upright?), among other problem areas.
RTs are not trained to treat and eval all these areas. They may pick up those skills over time, but there is a reason why OT is a graduate program. We are taught to look at all these additional aspects of what is needed for participation in activities of daily living.
RTs are also not trained in ADLs like dressing, bathing, functional transfers (we overlap here with PT), feeding (overlap here with ST), grooming.
And back to the original topic: no, we are not going to be replaced by RT. I would be more worried about our overlap with PT (their schools are emphasizing increased focus on function) or ST (not as much of a concern).
Edited:
Infonerd, while browsing other threads on the board, I realized you are probably asking more about RT vs OT from a mental health perspective. Very true, there is a bigger similarity between RT and mental health OT. However, we are losing ground in mental health as a whole, not just specifically to RTs. Schools are also altering their focus and slowly decreasing time spent teaching us about mental health.