https://www.pushsquare.com/news/2020/10/sony_launching_new_ps_store_on_web_and_mobile_this_month
https://www.psu.com/news/sony-will-launch-a-new-web-and-mobile-playstation-store-later-this-month-removing-ps4-ps3-and-vita-purchases-online/
https://www.androidcentral.com/psn-web-store-reportedly-being-updated-later-october-ps3-and-vita-games-will-no-longer-be-available
https://www.psu.com/news/sony-will-launch-a-new-web-and-mobile-playstation-store-later-this-month-removing-ps4-ps3-and-vita-purchases-online/
https://www.androidcentral.com/psn-web-store-reportedly-being-updated-later-october-ps3-and-vita-games-will-no-longer-be-available
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Sony has communicated to developers that it plans to launch a new PlayStation Store on the web and mobile later this month, which will remove the ability for you to purchase content for legacy consoles such as the PlayStation 3, PS Vita, and PSP. PlayStation 4 apps, themes, and avatars will also no longer be available through the web and mobile storefronts once the changes roll out, while content from your existing wishlist will be removed...and with it so dies any hope i had that BC will ever be extended to include any retro gaming. i've said it before,.. i don't think this is that big of a deal. what i'm saying is i think this makes it quite definitively unsupported now and forever.
The alterations presumably preface the introduction of the PlayStation 5; source code discovered on the official PlayStation website hinted that wishlists will be integrated into the next-gen console, so it's likely the manufacturer is completely rebuilding this feature. Sony's yet to reveal its new system's user interface, but following this week's hardware teardown, we can't imagine it'll be too far out.
While you'll no longer be able to purchase PS3 and PS Vita content from the PS Store on web and mobile, the platform holder is not shutting the storefronts down; you'll still be able to buy content for both consoles using their native PS Store apps, although Sony has been failing to display new releases in the PS Vita storefront for years now.
As for any themes, avatars, or apps you own on the PlayStation 4, you'll still be able to access those directly from your console. And it goes without saying that any content you've purchased for any of the aforementioned systems will remain in your download list and will be available exactly as it was before. As mentioned, this is almost certainly all in preparation for the arrival of the PS5.