Some use this Rambam to forbid vacation outside of Israel for those who live there (e.g., see R Shlomo Aviner at the very bottom of [here][1]).

Others are well aware of this Rambam but qualify it, e.g., 

> R [Shmuel Halevi Wosner][2] (Shut Shevet Halevi 5:173, cited bottom of
> [here][3]) writes that the primary prohibition of leaving the Land
> applies only when one intends to establish his residence outside of
> Eretz Yisrael, but leaving temporarily is more lenient. Yet, he
> qualifies this leniency and writes that there must be some sort of
> concrete need for the person to leave. 
> 
> Accordingly, it would be prohibited to leave Eretz Yisroel for a
> vacation if the trip does not serve a constructive purpose. It would
> be permitted if it serves a constructive purpose such as seeing the
> wonders and beautiful parts of Hashem’s creation, resting (when this
> cannot be easily achieved in Israel), and so on.


  [1]: http://www.ravaviner.com/2010/12/shut-sms-96.html
  [2]: https://en.wikipedia.org/wiki/Shmuel_Wosner
  [3]: http://dinonline.org/2015/07/17/here-to-stay-the-halachah-of-leaving-the-land-of-israel/