We all have those logs and it does not mean your device is managed. Here it is on my Mac:
Mar 14 03:51:50 airportd[182] [*] [0:MCXToolsInterface:<0x526>] Log file created
Mar 17 07:26:46 mdmclient[49704] [*] [501:MDMAgent:<0x23b4f2>] === CPF_RemoveProfile === system.ratings.digital_health_restrictions.system.ratings (user: xxxxxxx)
Mar 17 17:50:09 mdmclient[58017] [ERROR] [0:MDMDaemon] Process has been running too long (1758.7 seconds)
Mar 20 20:45:48 mdmclient[351] [ERROR] [0:MDMDaemon] Process has been running too long (1268.5 seconds)
Mar 21 18:08:44 mdmclient[11363] [ERROR] [0:MDMDaemon] Process has been running too long (1762.4 seconds)
Mar 28 17:48:32 mdmclient[98949] [ERROR] [0:MDMDaemon] Process has been running too long (1633.7 seconds)
Mar 30 17:57:22 mdmclient[25648] [ERROR] [0:MDMDaemon] Process has been running too long (1814.9 seconds)