Hello Jo,
There are no factual figures available to us to know if there is an increase in the number of incidents involving caravans.
There is, I am sure, a seasonal variation, but I cannot tell if there are more this year compared to last, so I think it is a bit presumptuous to assume there are more.
Big S,
Unless the car or tyre manufacture actually tells you not to tow with a space saver, then it is presumably actually ok. However like you I would not be happy doing it. I would certainly be taking things slower and easier.