Mini Toslink adapters... degrade sound?

Just curious, some digital gear, to save real estate, use mini Toslink connections.

We know that when using SPDIF Toslink, it is best to use true glass cable conductors, not the cheapie and ubiquitous plastic conductor ones.

Question, for those who have tried, do these adapters degrade the sound much?

https://www.moon-audio.com/toslink-to-mini-optical-adapter.html?gclid=CjwKCAjwq_D7BRADEiwAVMDdHtMNAW...

I cannot find a glass cable that terminates to a mini Toslink end...

Thanks in advance.