Paul George infamously coined the term Playoff P in the 2017 playoffs before being bounced in the first round. Playoffs have become due or die for NBA players with the regular season becoming largely irrelevant for NBA players. Players performing out of their mind has earned many players nicknames, most famously Rajon Rondo aka Playoff Rondo.
The Miami Heat started off their 2023 playoffs disastrously with losing to the Hawks in Miami for the #7th seed play-in. They then beat the Bulls for the 8th seed which would have them set up against the #1 seed Milwaukee Bucks.
Then... All hell broke loose with Playoff Butler playing like a mad man. Averaging 37 points, 6 rebounds, and 5 assists, Butler looked like the best player on the planet. He simply could not be stopped and willed his team to victory, regardless of who was or was not playing.
As a result, you have his base cards both raw and graded seeing massive gains over the last week. When you have a guy playing like Butler, it will have people clamoring for his cards regardless of the current market.