This is a bit weird from a legal point of view unless there were contract agreements we're not aware of. What I mean is that these games were released back then and a fee for licensing was paid to the FIFA brand/body. If for example a copy of FIFA 15 or 16 was sold in 2030 there's no breach of contract imo as the license to sell the game was fully paid already.It's a licensing thing. You can't sell FIFA games and profit from it when you don't have the FIFA license any more.
As I've mentioned there might be some terms in these contracts we don't know but I have a feeling it was exclusively EA's decision to remove these games. It's all about money, they probably saw that a lot of people are trying to get back to previous iterations of the game and ofc they want to stop this.
I'm really concerned they might pull the plug and prevent legal owners of these games to play them digitally through the platform. If this happens we'll all need to unite for a proper lawsuit against them.