One way to change this is to update the process step for "VI_ADS_ADSAccount_INSERT", "Create ADSAccount in ADS", so that for 'AllowLogonTerminalServer' the value is 'True', e.g.:
'Value = True' instead of the default, 'Value = $AllowLogonTerminalServer:Bool$'.
This would require making a copy of the default "VI_ADS_ADSAccount_INSERT" and making the required change.
To change the behaviour for user accounts brought in via a synchronization, the default process "VI_ADS_ADSAccount_UPDATE" can be changed to update 'AllowLogonTerminalServer'.