- Sure - looking at what Apple's silicon team is doing with ARM would make you think that ARM has nothing to worry about for a while. However, notice that Apple is the only one who is getting a lot done with ARM at the high end. Qualcomm, etc. aren't getting the same amount of performance. I believe that's because of the non-ARM stuff that Apple puts in their silicon efforts. Imagine in a few years, when the small companies designing and licensing RISC-V cores are not that small anymore - folks like Amazon (uses ARM cores in their servers) and Apple might have a serious alternative.
- I think open source models win in the long run, similar to Windows vs Linux, or closed version control software vs Git. The tooling around open source grows over a few years and then suddenly it feels like it's miles better than the closed options. I think similar stuff will happen with silicon.
- ARM themselves worry about this btw - not that long ago they created a website smearing RISC-V which was mostly full of FUD. Their employees revolted and made them get rid of that site: https://www.theregister.com/2018/07/10/arm_riscv_website/