Idea Summary
Right now, in 23ai, if you run the following command APEX says “No”:

exec apex_instance_admin.set_parameter('WALLET_PATH','system:');

Error starting at line : 1 in command -
BEGIN apex_instance_admin.set_parameter('WALLET_PATH','system:'); END;
Error report -
ORA-20987: APEX - Wallet path must be in the form file:<filesystempath> - Contact your application administrator.

Use Case
23ai now allows us to use the OS certificate store instead of mandating a wallet created by DBAs with orapki.

Preferred Solution (Optional)
Update the set_parameter code to allow the use of ‘system:’ as the wallet path if you are running it in Oracle 23ai or higher AND, by default on a brand new installation, just go ahead and set that parameter out of the box. Optionally, during the install, you could check if there is already a wallet path set, and during the output at the end of the install, you could add a message like the following:

We detected that you were using the old DBA-maintained wallet path in your previous version of APEX. We updated the instance administration to use the new 23ai and higher preferred way of using the OS wallet, and have run the following for you:
exec apex_instance_admin.set_parameter('WALLET_PATH','system:');
If you would like to keep your old settings for the wallet_path, then execute the below statement:
exec apex_instance_admin.set_parameter('WALLET_PATH','file:[WhateverValueWasThereBefore');
You should strongly consider moving towards the new OS system wallet instead of using a DBA-maintained wallet.