You do get an audible "DUAL INPUT DUAL INPUT" warning and some lights though [1]. It is never allowable to make sidestick inputs unless you are the single designated "pilot flying", but people can sometimes break down under stress of course.
The 777 and 787 before it are true fly-by-wire designs like the Airbus in question here; the 737 MAX isn't and never was. It just had a computer that was supposed to add artificial inputs under a very specific condition, so it could continue to fly like the older models under the same type certificate and not require extra pilot training. It turns out that the condition could be triggered erroneously, and the logic to determine the artificial inputs was deeply flawed.
The 737NG already had computer controlled feedback to the control columns, the MAX added computer controlled spoiler deployment (like the 757 and 767) and elevator trim.
That's applicable for one specific model of ADIRU (basically determines where the aircraft is in 3d space in terms of position, rotation, velocities, and accelerations) from a single manufacturer (Litton). These aircraft have dozens of computers for different functions, many of them with multiple manufacturer options. There are at least 4 different ADIRU makers that airlines have been able to specify at different times including the Litton.
The ELACs (controlling the elevator and aileron actuators according to the demands computed by other functions) are made by Thales specifically for this aircraft type and probably have a quite different design.
I’ve run into this exact issue several times with group projects at university in the 2010s, and each time recovery was copying chunks of plain text from backup copies into new documents as you say. Luckily by the time we got to the final year capstone project the whole group was happy to go with LaTeX. Not sure if these Word issues have even been fixed since.
I don't have a source for this, so take it with a huge grain of salt... but for some reason I have a memory of someone telling me that the older versions of Word saved and loaded documents by writing the bytes of in-memory data structures directly to files on disk, with not much in the way of marshalling or validation in the middle. Because it was fast, or something. You can imagine the kind of edge cases and oopsies that might result.
The new versions at least serialise to some kind of monstrous XML representation of Word's internal state, so while it's not going to win any awards for world's most elegant document format, it should be slightly harder to corrupt in subtle ways.
Certainly not just down to luck across the industry as a whole though. That particular type was exempt from a bunch of regulations, written in blood, that all the other popular types comply with.
I had similar problems with a local train app in Germany on Googles store. The organisation when asked said to install another app instead, that was not linked anywhere on their homepage.
[1] https://safetyfirst.airbus.com/app/themes/mh_newsdesk/docume...