They run Intel CPUs made within the last ten years so would be subject to this issue. But the performance hit is really dependent on the computing that you're doing. It's not a guaranteed 30% or a guaranteed 5%.

Are you doing a lot of really CPU intensive tasks that make a lot of syscalls? Most people aren't. If you are, you'll probably feel that pain. And if you're not, you probably won't notice a difference. And if you don't know you can either research if what you're doing typically is going to be affected, or wait and see.