Entering CTL 6100WL will cause most search engines to return Wacom Intuos wireless as the result. This means it is a wireless Wacom Intuos, and in my experience, these are extremely durable, but not indestructible. The maximum age of seven years is not particularly old, but constant intensive use can naturally lead to signs of aging.
If you don’t need a wireless connection to your tablet, i.e., you don’t need to use the tablet via Bluetooth, the OpenTabletDriver driver will provide you with all the tablet’s functions, so it’s worth a try. OTD drivers are considered excellent, but as they are not the manufacturer of the respective hardware, the people at OTD cannot always support all functions for every tablet, as the hardware manufacturers do not always reveal their cards.
Furthermore, yes, a stylus can break, and the pen release event not triggering could indicate this. Therefore, I would see if you can borrow a Wacom-compatible stylus from someone you know or test your own there, or if you can test your pen on one of the demonstration models at a store in your area.
Krita itself as culprit is unlikely, because if it were a Krita issue, then we would already be buried in lots of support requests of your kind.
But one thing came just to mind, in the case that you use Krita with Brush Smoothing, and have it set up to insane high values when using Weighted or Stabilizer, then some strange things can happen. Don’t use values above 70-80 for Distance of the Weighting option, and the same is true for the setting Delay of the Stabilizer option, at least if you don’t have an extremely powerful workstation and paint murals of far above 10k square-pixels in size. But the bigger your canvas gets, the higher you can go with these settings, but they can “offer” some performance impact.
Michelist