Computers are becoming architecturally more secure alongside just patching bugs. We have seen the move to using VMs with a minimal hypervisor, using separate security chips to hold sensitive info like encryption keys, Memory Tagging to detect and prevent memory exploits.

On the iphone for example even if you find a crippling bug in iOS which gives you full root access, there is still no way to get the device encryption key or face ID info because the secure enclave simply has no electrical connection that can pass that key to the OS.