On employer-provided devices, the employer should have access to whatever they want. Whatever you do on their devices employer should have access to because it is company's property and you should only use those devices to complete the task that is given to you efficiently.
On personal devices used at home on employer-provided networks, your employer should not have access to any of this data. If your network is provided by your employer at your job on your personal device I believe the employer should have to access to data that is collect only at work time. If you are home or after work your data should not be collected even if you are on the employer-provided network. 2. As a manager, data I would like to obtain from employees