By my count Tatum has not shown up to nearly 1/3 of the games played this season.
Out of the the 68 games the Celtics have played this year, and 61 Tatum payed in, he has left his shooting skills at home in at least 20 games. his latest off night was the 3-15 in Chicago.
If you want to be your teams #1 scoring option, that cannot happen on almost weekly basis.
Or to phrase it differently, your team will not be very good if your top scorer has a very bad shooting night every 3.5 games.