The My Little Pony web portal has been removed from Hasbro's website, along with those of Hasbro's other franchises such as Nerf and Transformers. The My Little Pony site was created in 2003 and was moved to mylittlepony.hasbro.com in July 2015, and it featured information, videos, activities, minigames and product listings.
Hasbro's website rework involves the consolidation of the website subdomains of all of its franchises, which I imagine is intended to reduce maintenance costs. Now, all of the products are shown on shop.hasbro.com, and all of the videos, activities and minigames are linked to from play.hasbro.com. Some information, such as the pages about characters, is no longer available anywhere on Hasbro's website, and can only be viewed through archival websites such as the Internet Archive Wayback Machine and archive.today.
Note that this change is not an indication of anything specific to the MLP brand, since the same change was made for the sites of Hasbro's other franchises as well.
Screenshots of Hasbro's current web portals are shown below.
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