According to Google, Stewart started smoking in 1955 and quit in 2000. Smoking doesn't really appear to be thing in the Star Trek future.

The actor of captain Picard

Do you honestly not recognize Sir Patrick Stewart? No shade, it’s just wild to think there would be people who don’t recognize him at all, given the length and breadth of his career.

In answer to your question, I can’t speak for Patric Stewart, but my guess is that he chose to play the scene that way because it’s likely that very few people in the Federation smoke, and that’s probably doubly true for people who spend most of their time on a spaceship. My guess would be that Stewart was trying to indicate to the audience that smoking would be somewhat of an anachronism in the 23rd century.

Is the active ingredient in holographic cigarettes synthatine?

Patrick Stewart doesn't smoke tobacco and to my knowledge never did habitually, but he does consume weed products every day to help with his arthritis

In the blu ray audio comentary tracks for Star Trek Picard Season 3, Jonathan Frakes and Brent Spiner talk about taking smoke breaks on the set of TNG. They mention that Patrick Stewart joined them very infrequently.