To make Ubisoft more money, to get people using their 'amazing' service, more people on uplay, more possible sales for them.

What is the point of Uplay?

Ubisoft Connect (formerly Uplay) serves as a combination of a free reward system (formerly Ubisoft Club) and online profile system for players of Ubisoft games. While playing Ubisoft games, players can complete in-game achievements which earn points towards their profile.

What happened to Uplay?

Ubisoft Club and Uplay PC will become Ubisoft Connect on October 27th 2020. ... We will also unlock all rewards for older Ubisoft titles that will not fully transition to Ubisoft Connect.