Hyundai Group have always aimed to rival/beat Japan automakers (TMC in particular) partly because TMC being the best among automakers and also partly because of general rivalry/bitterness that South Koreans companies tend to have towards Japan counterparts. Samsung has already beat the hell out of Japan Tech and Hyundai wants to follow the same footsteps. Still, it is way off for them to go head to head with TMC but like I've discussed in other threads they are climbing up the ladder really really fast (much faster than I would like them to be LOL).
Below article about how Hyundai came from sourcing engines from Mitsubishi to building the former Genesis luxury model shows how far they have come and how their development philosophy always has been.
Once dependent on borrowing other automaker's designs, Korean automaker Hyundai is now reluctant to reciprocate. Read more at Automobile Magazine online.
www.motortrend.com
In that article, I would like to highlight this:
"It all started in 1990," recalls Dr. Lee, "when Toyota launched Lexus. We were just spectators, but we thought, 'Why couldn't we do that, also?' At the time, our daydream seemed laughable, but through diligence and hard work, our dream has come true"
All that said, going back to the original question "will the Genesis hurt Lexus?"
No - for now.
Probably (very likely) - in a near future.