I don't think physical media is going away, but Gamestop may be another matter. I don't think they are managed well. Whenever I go into a Gamestop nowadays I see this tiny little section for Switch games with huge sections for PS4 and XB1 games. The Switch basically has the same shelf space that the Wii U did. Is it any wonder why Amazon always over represents Switch sales? Tons of Switch customers go to Amazon, because Gamestop is just not going to be their store. They can get the Switch games they want at Amazon, but not at Gamestop.
Surely Gamestop knows that the Switch is selling a lot better than the Wii U, but they haven't changed their behavior accordingly.
You must have a bad GameStop. The one near me has the Switch section out front and it's got to be the same size as the PS4 and XBO sections. They also have a decent sized section for Amiibos.
Of course, who knows if your store is basing their layout on regional sales or it is just poor management of that store.
I've always had a good experience at GameStop. Well, minus the hounding about preordering. Sometimes you get a good employee, who knows people hate it, and he'll ask once quickly and be done with it. But, other times you'll get the overzealous employee who asks you, you say no, but will go through the upcoming releases to try and get you to preorder anyway. I know corporate has quotas for them, but God, they have to learn that turns people off from coming back.