There is some debate about the validity of that statement. The highway speeds mapping is certainly part of hda, but is mentioned specifically as only part of it.
There seem to be other parts of this than just that, such as how long the car will sit in traffic not moving and then start going again.
The manual and Hyundai's advertisement does a HORRIBLE job of differentiating the features here.
Yes, it is confusing. And Hyundai has made things worse. Watch the two official Hyundai Palisade videos below. Pay close attention to the shots of the fully-digital dashboard as they demonstrate the features.
The first video is about LFA (Lane-Following Assist). They very clearly state that it centers you in your lane. They also clearly explain how the little steering wheel icon is what indicates that LFA is enabled. And that it goes green when LFA is active, and white when it isn't. Watch carefully when they demonstrate that: the dashboard shows that HDA is also enabled (timestamps 1:10 and 1:28).
Now watch the second video about HDA (Highway Drive Assist). They state that it also helps with lane centering. And they explain the whole speed limit thing I described in my earlier post. But the dashboard at 1:43 looks almost identical as the one in the previous video (it actually isn't, but it's very similar). The lane-centering portion of this video explains literally the exact same thing as the previous video...
The manual also states that HDA does lane centering. But at the end of the HDA section, it refers you to the LFA section for more info on lane centering and steering, after giving a bunch of info on GPS and speed. Go figure...
So what to believe?
Personally, this is one case where I call BS on Hyundai. I think the marketing people who made these videos aren't very clear on what the systems do and it seems to me that HDA has to do with speed only, despite what that second video shows. I know from personal experience that LFA works without HDA - you get the exact same steering wheel icon and behavior. I happen to live near a highway that didn't have qualify for HDA until I updated the maps, so I have used LFA with and without HDA on that highway. I couldn't detect a change between LFA with and without HDA.
Maybe I'm wrong and HDA provides an extra level of lane centering and steering assist when HDA is enabled, even if I couldn't tell the difference. I certainly wished Hyundai clarified things. Maybe when they're finally done updating the manual and it shows up again on myhyundai.com.
LFA video:
HDA video: