I have similar feelings toward ROS, but I don't have experience with industrial alternatives. Would you be willing to elaborate (insofar as you're allowed to) about what made the "step-function" level of difference between ROS and the internal systems you've used? Or on what you would want to see in such a next-generation system?
Robotics is very much split into research users and industry.
In industrial automation you buy a device (say a sensor or programmable logic controller) that comes with a few supported protocols. Typically a field-bus for realtime communication. And for the fancy ones also OPC UA (ISO 62541).
I don't know automation vendors that sell devices with ROS-support out of the box. With the use of Python it must be hard to get ROS safety-certified.
OPC UA is like a merge of ROS (channels for PubSub communication) and "CORBA done right" (an object-model that can be transparently interacted with over the network).
Full transparency, I maintain open62541, an open source implementation of OPC UA.
When I was using it, I didn't get any vibes of "anything done right", I actually find OPC UA to be a horrible (and underdocumented) mess. This can also be seen in nearly all the various language bindings, just as if nearly everyone has had some problems with the protocol or ran out of steam at the most basic things.
open62541 is really nice though, thank you for your work.
I do find any comparison of ROS and OPC UA a bit weird though, but that maybe depends a little on your use case, especially if not strictly talking about what you mentioned.
