Personally I despise adulterating hold em in any way. I am, extremely so, not a fan of stand up game, 7/2, etc.
The entire point of hold em is it's a solved game and meta strategy these days. If we're playing hold em, then let's play some damn hold em!
On the other hand, there's a reason when you walk into a room the entire hold em table looks board, exhausted, and on the verge of crying/screaming/going to sleep. Meanwhile the other tables are loud, boisterous, crying laughing, etc. All these nonsense add ons to generate action, break up the monotony, create some fun - to me, just try mixed games at that point.
edit - to say that my experience is very limited. but my personal experience is when someone is running these I often think of as being poorly done and trying to generate *something*, whether that's fun or simply action or someone getting stacked. I don't think the games are necessarily being cultivated in a meaningful way, it's just tossing things against a wall and see what sticks without any strategy. I can see the point of slowly trying things like maybe adding 1 double board hold em per hour to test the waters. But again, all we're doing is tossing in dead money and a second board - essentially a luck roll. Personally I think most groups would do far better doing maybe a triple hand hold or something similar once an hour - changing the actual dynamics of the hand more so than just "action". Even better would be setting aside the last hour or last rotation (or two!) for some extremely light DC to dip the toes.