1. I am bucking the trend ! If you look at it, Microchip just licensed MIPS a few years ago when they could have licemsed ARM. Cores are really immaterial, it is the AXI eco-system that matters.
2. In the case of Freescale, they havd chosen to play both cores, PPC for higher end and ARM for lowe end. Thsi will remain so at least for the next 5 years. The T4240 is just getting design production wins (started shipping just a month ago in production). Their encryption product, the C29x is also PPC. No way in the higher end networking world and the telecom world, parts that got designed in in 2014 will be swapped out that easily.
3. The ARM64 cores are simply not mature enough for for high end virtualization and other such features. The e6500 core is pretty well tuned for networking apps (shallow pipelines for starters). The A57 is one size fits all. You cannot seriously tell me the A57 core can take on the e6500 PPC core in networking and the IBM Power8 in servers ! If you believe that I got a bridge in Chennai I want to sell you ! Not as impressive as the Brookly bridge perhaps ...
Bottom line for commodity products there is a universal move towards ARM for SW reasons but at mid to higher perf levels, that trend is not that clear. Broadcom is on MIPS , FS is on PPC, Cavium is on MIPS, EZchip is custom and only Netronome is partially on ARM. Intel does not count yet. Also notice none of them have an AXI framework. Dumping a core is easy, dumping your NoC and I/O subs-sysyems is a whole different ballgame. In that case, just switching to an ARM core does not buy you much. Would love to look at Freescale's source code for the processor.
Does not seem like a trend to me.
And repeat after me a 100 times - "I shall stop listening to analysts and start listening to engineers who actually design these systems"