I like new positions and moves, because they keep the sport interesting.
When you roll a lot and for many years, always doing the same thing can become quite boring. It is in those situation that it is fun to practise these new thingies and maybe you are even lucky to add some of it to your own bjj game.
The difficult part however is that to many new students focus only on those new fancy moves, because they are the hot topic at Sensei YouTube's academy.
Leading to people who can spin into worm guard and berimbolo, but have no clue how to hold a basic sidecontrol. I think they often forget that their idols in the sport went to some years of doing all those basic things before.
Anyway, as a teacher it is a tough decision because you want your students to get used to those new situations and the only way to do that is having students that do those moves. No way to learn how to defend if nobody is attacking you.
What I personally prefer, is students that stay close to what I teach as basic curriculum and then focus on one positions (okay, maybe two) that they want to make their own. That way they develop a good base and add something where whole the academy can benefit from.
Just my thoughts,
K