Based on point per possession, these guys are the top 5:

(Player, Poss, PPP)

• Kristaps Porzingis, 2.1, 1.56
• Jayson Tatum, 2.9, 1.29
• Tobias Harris, 2.3, 1.21
• Anthony Davis, 4.4, 1.20
• Karl-Anthony Towns, 3.2, 1.18

https://www.nba.com/stats/players/playtype-post-up?CF=POSS*GE*2&dir=D&sort=PPP

Top 5 players with the most post-up possessions are:

• Nikola Jokic, 6.8, 1.13
• Joel Embiid, 6.1, 1.06
• Bam Adebayo, 5.0, 0.93
• Anthony Davis, 4.4, 1.20
• Julius Randle, 3.5, 0.90

https://www.nba.com/stats/players/playtype-post-up?dir=D&sort=POSS

AD is the only one being in both lists. Bam and Randle looking not very efficient posting up, but they still do a lot. Jokic, as usual, has the most post-ups with very respectable efficiency, shooting 57.3% from the field.

Other notable and interesting names:

• Devin Booker, 1.0, 1.56
• SGA, 1.7, 1.37
• Dario Saric 1.1, 1.29
• DeMar DeRozan, 2.3, 1.14
• Rudy Gobert, 1.4, 1.11
• LeBron James, 1.8, 1.03
• Giannis Antetokounmpo, 3.5, 0.82
• Zion Williamson, 3.2, 0.83
• Victor Wembanyama, 2.9, 0.89

The least efficient players with at least 1 possession per game:

• Evan Mobley, 1.1, 0.52
• Anthony Edwards, 1.1, 0.61
• Nikola Vucevic, 2.9, 0.72 (WOW)
• Jeremy Sochan, 1.2, 0.73
• Isaiah Stewart, 1.2, 0.74

https://www.nba.com/stats/players/playtype-post-up?dir=A&sort=PPP