In 2025 people will still be talking about how the game is going to end soon, but it won't... ^o^
Depends what you been by end.
I don't know whether or not it'll last that long, but I can see the following years nothing but perpetual content drought with paid subs,until enough people get sick of progressing in a world with no future and SE pull the plug. At the point of the former, the game has ended really, it's just gone into some kind of paid purgatory.
As for the chance of an expansion, if you believe there to be even a small chance of this, you're hilariously naive. Square Enix aren't stupid, if they outright said "nope, no future bro", or something to that effect people would probably give up on the game, and subs would be lost. Instead, they word it as a possibility, to fool you, while maintaining a position that offers no promise. They have no intentions of another expansion, but hey, if they appear to, it'll hold on to some subs for as long as possible.
And before anyone says "well they could have ignored responding about expansions"; there were multiple questions concerning expansions and the games future, ignoring them all would have been bad. Saying they're considering an expansion though is an effective measure of throwing people a bone of sorts.