Dude. 23/6/5 on 42%/34% splits isn't "good" for a superstar player of his regular season caliber. It's profoundly disappointing. You act like he plays decently enough, but is eventually just overmatched, when he's often a (the?) key contributor to their demise.
He shot under 40% in that infamous 2015 Clippers series and was riding the bench during Josh Smith heroics. In the obvious aforementioned 2017 Spurs' series, it wasn't just the pathetic Game 6; he shot 41%/31% for the series (3-17 in Game 2). In 2018, against Golden State, he shot 41%/24% (on 11 3PTA a game). The following year, he lost Game 6 at home to a KD-less Warriors. So yeah, we remember the stinkers first because there's been so many, and he hasn't broken through yet.
Of course he isn't always bad. He's played a shit ton of playoff games. But consistency is a huge part of what makes a superstar a superstar. You generally have no fucking clue what you'll get out of him.
He deserves credit for a HUGE game after looking washed in round 1. He's in a great spot with little pressure. He's no longer his team's best player. Win the series, and he'll get serious props for setting the tone by stealing Game 1 practically singlehandedly. Lose, and it falls on Embiid or his injury.