last time I checked the platform support for drafting 18.1 i noticed the Wacom tablets being supported go to the series Intuos3. (link)
when I check the website of Wacom I see that the Intuos3 series is no longer in their product range. (link2)
So i think PTC should spent some time reviewing the available tablets and update the list of supported tablets.
I still frequently see users who draw with their old tablet (mostly with serial port), desperatly asking if their tablet will still function after an update.