It's a bold move. With super soldier serum, Chris Evans' Captain America is able to go toe-to-toe with all nature of otherworldly threats, including the Chitauri, Outriders, and a fully-powered Thanos in Avengers: Endgame. He wouldn't have been as effective without the serum.

Anthony Mackie recently confirmed that his version of Captain America, Sam Wilson, will not take the Super Soldier Serum in Captain America: Brave New World. He stated that Sam remains a regular person,

Anthony Mackie confirms Sam Wilson will not take the Super Soldier Serum in Captain America: Brave New World, keeping him a grounded hero.