Face it, you are not even fully patching your own systems. Assuming that your customers or users will try to patch their systems is unrealistic.
If you are delivering any product that contains software, you need to think about how you will patch the thing. Tesla just discovered a problem with the pinch protection in their power windows. Cars with electric windows must have an “automatic window reversal system” that detects if it is about to pinch a finger or worse. Tesla found its system would not always be within the required parameters and pushed out an over-the-air update to more than a million vehicles. Elon Musk took to Twitter to fume about the fact that such a fix is technically a “recall.”
On the other hand, more than a year after the vulnerability was discovered, there are still more than 80,000 vulnerable Hikvision cameras connected to the internet. Besides the fact that everybody can view their footage, the built-in Linux server is probably also mining crypto and sending spam. The owners could not be bothered to pull the thing down from the wall, connect it with a cable, install updated firmware and mount it again.
Be like Tesla, not like Hikvision.