Why can't we use static objects?

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At least, CI should have:
1) Proper, basic authentication system.
2) Use of namespace
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The use of a "default" authentication "system" is only acceptable if it can be disabled by the developer.  The developer might not want to use the default authentication and must be allowed to replace it with another auth system.  I think this could be implemented as a simple configuration flag. 

That being said:

My personal choice would be to NOT include authentication with CI.  I think it is better left as a third-party tool to be integrated by the developer.  This avoids "code-bloat", which we see in competing frameworks.

namespaces are very desirable in CI 4.0, even if it mean CI becomes more complicated for the first-time user.

CI 3.1 Kubuntu 19.04 Apache 5.x  Mysql 5.x PHP 5.x PHP 7.x
Remember: Obfuscation is a bad thing.
Clarity is desirable over Brevity every time.