I’m not sure, but some parameters probably don’t use the same resolution as the envelopes. Also, it is probably not suitable for the tracker’s own performance.
In addition, there is no advantage to draw an envelope automatically when the parameters written on the tracker exist. Either you use the parameters or you use the envelopes. The tracker will take priority to one thing over the other, I suppose, if they both conflict. Or put another way, why do you write parameters if you can do it with the envelopes.
That said, I have to say that automation in Renoise is very powerful. However, it is a pity that the automation editor is not better. I would pay a new license just to see the damn improved editor!