Soon we shall find out. I'm actually feeling optimistic, I'm not sure we're going to get that particular signal on Monday, but if Apple doesn't decide to lock down the OS completely with an ARM transition, I don't think they ever will and the more pressing concern will be whether Apple decides to keep the Mac line at all down the road.
That said, I keep virtual machines of operating systems that interest me up to date. I'm between 9front and Haiku OS as my eventual replacement, and I still might switch to a ThinkPad running 9front for my next computer regardless of what Apple announces. I'll still have much of what I value on a Mac in my iPad, and my laptop is essentially for writing, programming and backing up other hardware.
That said, I keep virtual machines of operating systems that interest me up to date. I'm between 9front and Haiku OS as my eventual replacement, and I still might switch to a ThinkPad running 9front for my next computer regardless of what Apple announces. I'll still have much of what I value on a Mac in my iPad, and my laptop is essentially for writing, programming and backing up other hardware.