It's not the OS support that is of concern. The concern is if application developers continue to support them.
Some apps were still 32-bit only until a couple years ago, like Office. Developers tend to lag at supporting new stuff and dropping old stuff unless supporting the old stuff costs them extra.
I'd be surprised if developers turned off the x64 builds quickly, so long as they weren't spending gobs of time building them locally, or aren't using a bunch of assembler (geez, I hope not). Bitcode can help smaller devs here as well.
Parallels/VMWare and similar stuff that sits on bare metal more than most apps are probably going to be the first to drop Intel support on macOS.
I'm glad that finally Apple have announced the ARM transition. Also great to know that Apple will be supporting Intel for years to come, especially since Apple are planning more Intel based products.
ARM and Intel can live side by side.
Yeah, although this now puts all of the Intel models Apple sells on a 2 year clock. Within 2 years, no new Intel Macs will be available if they hold to schedule. So they won't be living side by side for long on the shelves. If you are in line for an upgrade soon and want it to be Intel so you can ride out the transition, do it sooner rather than later, IMO.
My main worry is that their workstation-level hardware will lag and wind up too slow compared to Intel/AMD offerings. Especially since they were mostly showing off the A12Z, which is a fine processor, but more laptop-class than something that can replace the highest end iMac, iMac Pro or Mac Pro. Also, they mentioned nothing about AMD GPUs (internal or external).
Unlike with Intel, they aren't switching to something that has a full lineup ready to go, so there's some really big question marks that they really should have considered addressing for the prosumer/professional end of their market. Hopefully we get more nuts and bolts during the sessions rolling out this week.
Complain about Apple’s motivations all you want, but I am ready for some good old fashioned change and this is it. Better than poking their other eye out wasting time with AMD and that bag of hurt. This is going to be exciting, thrilling and somewhat terrifying. Those of you who hate change, please see yourselves out.
Oh, I get their motivations, but I think if the complaint is that Apple hasn't
demonstrated that it can replace R9/i9 or Threadripper/Xeon class hardware with their in-house silicon, there's a point. They haven't. They should in order to help demonstrate the value here.
But honestly, if going to Apple silicon means I can get a 16" MBP that runs as hard as the i7 in the base model, but also includes the 5300M or similar, and doesn't spin up the fans every time I do something remotely taxing? I'm in.