A company can lock the hardware but not the software, or lock the software but not the hardware? I’ve not heard this idea before, it sounds like an extremely lo

A company can lock the hardware but not the software, or lock the software but not the hardware? I’ve not heard this idea before, it sounds like an extremely logical idea. It would easily be achieved by splitting apple in two. I wonder if there are any downsides to that? The “walled garden” of hardware and software does have some benefits, but the cost to society is too high.