@User Problem with wirebonded chips like QFP, QFN for high speed signals is that the wires used for bonding have so-called self-inductance. Also the length of the bond wires will be different so different inductances. Also the routing in the package is typically not length matched etc. and will also cause unknown extra parasitics. I don't have experience with flip-chip bonding but I would suppose the also the RDL design needs to be carefully done for high speed signals.
I am into retrocomputing so for me high speed signals are not important but the limited number of the proposed WCLP is limiting for my applications.