The current Software version is actually 1788 but it isn't possible to install this version in the previous Infotainment Device, which has the suffix B. If you go into Settings on your Infotainment system menu, you will be able to identify what type of Device and Software version are installed in your vehicle. See the first and third lines of the attached photograph, under System Information.
The previous Device can be updated from 1664 to 1668 but that's a big update and needs to be done at the dealer's. There is also a 1666 Version, which was an interim fix and this, too, can be updated at your dealer's to 1668. It works in some cars but, by no means, all of them.
I am led to believe, that the 'D' Device was installed in all Golfs manufactured after Week 48 of 2020 and it is currently running the 1788 Software version. I also understand that further updates, by VW, are under development.
The Update Software button at the foot of the display screen is for minor updates only, and this will not update your system from 1664 to 1668. Finally, please note the above mentioned update versions apply only to the Infotainment System (which, admittedly, does link to other systems in the car) but there at least another 5 ECUs in the Mk8, and not all of the updates are visible on your screen or are directly linked to 1668 etc.
I hope this helps.