Have Curry sit or Brewer sit? You can choose only one. Honestly, I'd rather have Brewer not play. Any other "would you rather"s?
Have Curry sit. While Brewer normally gives the opposing team 15 or so points, Curry managed to score 20+ in one half.
How bad Brewer has been is a bit more of a meme by angry fans than an actual effect equivalent to giving the other team another MVP. Don't get me wrong, he's a big negative. Just as one statistical reference, Curry's lineups win by an estimated 12.4 points per 100 possessions more than they would with a totally average player replacing him (via BPM). Brewer's lineups lose by an estimated 3.1 points relative to an average player. So Brewer is not like handing the other team a Steph Curry's worth of points; he's more like spotting them a free less efficient star like a John Wall or an Isaiah Thomas, or a high-quality role player like a Jae Crowder or a Danny Green.