The new Lyrik is the fork the Pike lauded as being. Stiffer, plusher, more controlled. Given the relatively small internal changes the results are significant.
I recall reading that a 170mm Lyrik is about as stiff as a 150mm Pike, which is far from a massive difference. I think the bigger difference is in the air spring, with the Lyrik having more negative volume.
The 2018 Pike has the same air spring as the Lyrik (and the damper has always been the same) so it purely comes down to chassis stiffness/strength differences in the newest version.
The 2013-2017 Pike does feel a lot nicer and behave better with a Luftkappe to improve the air spring by increasing negative and decreasing positive volumes.