I remember reading somewhere that we will get another Twist in one of the upcoming objectives, can't remember which. It certainly hasn't been as frequently included lately as it was in the earlier states of the game (Core--Edge and end of Hoth cycle). It certainly is one of the most-defining/important cards (is that changing?). Of the sets with Twist, most (if not all, I can't speak to how the game is played in different metas) still see fairly regular play:

From Core:

(DS) Defense Protocol, Recon Mission, Council,

(LS) Core Leia, Secret of Yavin 4, Hit and Run

Hoth Cycle and Edge of Darkness:

(DS) Killing Cold, Lucrative Contract, Tatooine Crash,

(LS) Asteroid Sanctuary,

Echoes to current:

(DS) (none)

(LS) Forward Recon,

I'm seeing more and more decks online without Twist. Do you think it will keep getting pretty infrequent re-printings? Will other fate cards take over?

I think its inclusion should be sparingly and never in an already powerful objective set. The best part of any card game is deck building and making a hard choice to include, for an example Secret of Yavin 4 over another objective set that may be "stronger" for the Twist of Fate is a great deckbuilding choice this game provides.