I think making the game free is smart move.

Nothing is ever truly free - infants were a 'free' update to the Sims 4 but they were arguably the most boring lifestate available unless you shell out $40 for the Growing Together EP so that you can have milestones, events, playmats, changing tables, more furniture and clothing, etc. But without the EP, pretty much just watch and listen to them fuss and cry until you age them up to the next stage.

You will spend more money on a 'free' game than you can possibly imagine.