Well, that’s a solution, but not a particularly great one.
In theory, you could actually reduce security. Some people might have stricter permissions than 755/644, and some scripts actively make that kind of recommendation, like WHMCS: https://docs.whmcs.com/Further_Secur…ation.php_File
Also I’d imagine (depending on the type of customer – which only you know) you will get users asking why their permissions were changed.
A better solution is to identify the problems being caused by “unsafe” permissions, and tackle those.
For example – if it’s a website getting hacked, consider a security solution like Imunify360 or ConfigServer eXploit Scanner.
If it’s spam (as a result of getting hacked), consider better tuning the server to handle such cases: https://docs.cpanel.net/knowledge-ba…t-email-abuse/
Additionally you should consider educating your users on the use of safe CHMOD permissions and basic security practices (i.e. keeping software up-to-date, using strong and unique passwords, etc).