It's the latter. Displays of all types have been able to handle multiple sources since forever. The only people who want this are sysadmins trying to troubl

It's the latter. Displays of all types have been able to handle multiple sources since forever. The only people who want this are sysadmins trying to troubleshoot A/V systems or plug into a server and college students who want to use a laptop as a screen for a gaming system. Neither of those groups are large or make the laptop manufacturers much profit so they're not going to be catered to by the OEMs.