That is often seen for Android games. Though those ususally can get loaded on an Android device without a store.
As an example for a multiplatform game, Baba Is You is available on Switch console and mobiles stores, but there is no link to those stores on the game page and on Itch are only the PC versions.
Actually, how usefull would those links be? Mentioning an also available on Switch should be enough, if so desired. I am not even sure if it is possible to deeplink games. Is this used for people browsing websites on their console, so they find the game in their store? I know it works for google play store, but the console stores?