I do not think it is the toslink cable itself that is limited to 96, rather I think some early versions of the input and output sections were the limiting factor to 96.
However no digital expert here by far.
I have always used spdif output and that shows up on my dac as 24/96 because my dac does not support the full MQA unfolding which is the only way you would get 24/192 through a bluesound product or to use its own onboard dac and output via single ended analog outputs to your amp. But to my ears I found the sq to be inferior by far compared to a good outboard dac.
However no digital expert here by far.
I have always used spdif output and that shows up on my dac as 24/96 because my dac does not support the full MQA unfolding which is the only way you would get 24/192 through a bluesound product or to use its own onboard dac and output via single ended analog outputs to your amp. But to my ears I found the sq to be inferior by far compared to a good outboard dac.