The Dell U3219Q monitor has a (rather rare) feature that gets rid of the need for a KVM switch for me entirely. It has both an USB-C input and an USB3 upstream

The Dell U3219Q monitor has a (rather rare) feature that gets rid of the need for a KVM switch for me entirely. It has both an USB-C input and an USB3 upstream that can be combined with either DisplayPort or HDMI. It also has signal auto detection. When I'm starting up my PC, it will use the USB connection from my PC via USB3 upstream. When I power up my work laptop, it will take USB from its USB-C connection. That even eliminates the need to push a button to switch. I'm really happy with this setup.