As of May 1, 2021, the GoCenter central repository has been sunset and all features deprecated, with the reasons detailed in a deprecation blog post. The blog highlights the performance advantages GoCenter provided in downloading Go modules compared to downloading directly from version control systems. By setting the GOPROXY variable to GoCenter, users could significantly speed up module retrieval due to optimized protocols, reduced HTTP calls, and elimination of the need to recreate modules on the client side. Without the GOPROXY variable, the Go client has to resolve URLs, handle HTTP redirects, and parse HTML, which is more time-consuming. In contrast, GoCenter facilitated a straightforward one-request process to obtain module information, and downloading zipped files was faster than performing a git clone. Additionally, GoCenter simplified the process of constructing modules by directly downloading necessary files, thus avoiding the need to calculate checksums and generate metadata, offering a more efficient alternative for managing Go modules.