Predatory licensing agreements and cloud software which presumably allows the company to access/steal designs.
I've had an MK3S+ for years and even though it's a primitive machine in comparison to the current Bambu hardware I see no reason to upgrade to something else. It just keeps printing whatever I throw at it and the results continue to be very good. In fact, I seem to have better luck with it than the Bambus I sometimes use at various hacker/makerspaces.
If you just look at the numbers (speed, volume, ...) against Bambu hardware they're not as good, but the reliability and simplicity make up for it IMO. The main missing feature is multi-material support, but that's something I'm not really interested in due to how wasteful the current technology is.