There are comment as below on the datasheet.
"ADM3483/ADM3488 are more tolerant of imperfect termination."
Is this meaning the termination resistor is not required?
Adding termination resistors is recommended for long cable runs to prevent reflections and data errors.
When two or more drivers share a pair of wires, each end of the link has a termination…
When two or more drivers share a pair of wires, each end of the link has a termination resistor equal to the characteristic impedance of the cable
The slew rate limiting feature for the ADM3488 reduces the chances of reflections. Other parts that are not slew rate limited, and have fast driver output waveform edges, are more likely to cause cable reflections.
In an improperly terminated system the ADM3488 slew rate limiting feature will be an advantage.
However, the slew rate limiting feature does not remove the need to terminate your cable properly.
You still need to ensure that your cable is properly terminated.