Shari Redstone’s Paramount Global is seen as having reached a grow-or-sell crossroads that has the potential to set other transactions in motion — the pinball effect when one sizable company puts the “For Sale” sign out. (For the record, neither Paramount Global nor Redstone’s National Amusements holding company has commented publicly on the matter.) The wave of speculation about the future of Paramount comes as the entertainment industry is working through a massive transition when it comes to the way movies and TV shows are produced, distributed and monetized.