Controllers should have a higher resolution. With only 128 values, filter sweeps have ugly gaps.
MIDI has 14-value CCs anyway, it’s just that few controllers generate the messages. I don’t k ow how many synths respond to them.
It is impossible to create smooth filter sweeps with regular CCs without further smoothing on the receiving end, because the human ear can differentiate between many more than 128 frequencies.
And yes it truly isn’t a problem, as plugin developers have long since interpolated the 128 steps. If it were a problem, you’d be hearing choppy sweeps in every song and film score out there.
That's the point. It is not an issue for you, because it has been solved in certain receiving software that you use. That does not mean that the issue does not exist, but that it can be mitigated if you use software that allows that and smoothes the sweeps.