We’re not talking about a larger trackpad, but rather the patent suggests that the entire lower half of the MacBook could double as a trackpad surface (except the keyboard area, presumably). This means that users could essentially touch on anywhere around the lower half of the laptop to register an input.
The patent also suggests that the sides could act as secondary and tertiary trackpad areas that can offer up functionality when needed. In a way, it might be similar in concept to the Touch Bar where it could switch up functions depending on the app being used, so for example when browsing the web, the left and right sides could act as its navigation.
That being said, there’s no telling if Apple plans on making this trackpad patent a reality. The company has tried to reinvent the way we use laptops like with Touch Bar, but unfortunately while it was promising on paper, it simply did not live up to the hype.