There seems to be at least 3 different types of kedushas haretz:
1. HaShem tells the Avos about inheriting the land of Israel and what that refers to is after mashiach comes…There are different descriptions in the Torah that describe E”Y as being more than even in the times of Yehoshua and that I believe is going to be realized after Mashiach.
2. There is the Eretz Yisroel of the times of Yehoshua (post Mitzrayim). This was only “l’shaa” for a period of time and after we were exiled, it lost its halachich kedusha.
3. There is after Galus Baval in times of Ezra that is even less than what we first conquered in the times of Yehoshua. This is the official "borderes" tht we have today.
= There are halachic nafka minas in terms of sheeves and other halachos that are relevant to E”Y…there still seems to be some level of kedusha as regarding sheeves at least the rabanna do assur working the land that was considered E”Y from Yehoshua etc.
Very interesting! I believe Terumah in included as one of these "other halachos". I think it is only D'rabanan, however, there is a mitzvah to take off terumah in E"Y and not in places outside of E"Y.