Fallout 76 had an incredibly rough start, littered with unfinished parts of the game, Bethesda's PR blunders and overall terrible experience for the customers. Some suggested the only way to save it is going free to play, which may happen.
Fallout 76 sold poorly and that is sort of a public secret by now as several retailers were left with stock they couldn't get rid of. Some customers even went so far as retailer shops because they couldn't get a refund on it.
All of this could contribute to EB Games pulling Fallout 76 off their shelves entirely, along with any digital copies of the standard edition. The more expensive editions are still up for sale on their website, but standard editions come only in the form of pre-owned games.
Normally, it would just be another day in retail where a product that didn't sell gets pulled off the shelves, but some people, such as YouTuber TheQuartering have different theories. He this could hint towards Bethesda preparing to convert Fallout 76 to a free to play model, simply based off EB Games' decision making.
TheQuartering proceeded to investigate further, and figured out that Amazon had only one PlayStation 4 copy remaining in stock, just two months after its release. Considering that this is a supposed AAA title, it was weird that Amazon wouldn't replenish their stocks, which led TheQuartering to believe that this could potentially be another sign that standard edition copies will not be sold anymore.
Something similar happened with the PC version on Amazon, where there was only 20 copies listed at the time of making the video. Be mindful that TheQuartering warned any viewers that there may not be any correlation between Bethesda's plans and the lack of Fallout 76 stock, as this is only a theory at this point.
Still, with a player base that never bloomed, ban waves all over the place and negative press all around them, it would be the next logical step for Bethesda to turn Fallout 76 into a free to play title.
This would remove the massive barrier where no one wants to pay for the game after all the blunders, but the company would still need to find a way to deal with dissatisfied customers who already paid full AAA price for it, as well as a torrent of hackers who are bound to hop in, should Fallout 76 ever become free.