Why do new computers have no line-in jack?

New computers often lack a line-in jack due to the increasing use of digital audio interfaces and USB devices, which offer higher quality and more versatile options for audio input. Many users now rely on USB microphones or audio interfaces that provide better sound quality and features, making traditional analog inputs less necessary. Additionally, the trend toward sleeker designs and reduced physical ports has contributed to the omission of line-in jacks in favor of more compact and streamlined units.