About get_instance()

Hello world!
I am currently using Codeigniter 4. But I find out that "get_instance()" method has been removed.
So my question is:
- why is "get_instance()" not present in Codeigniter 4 ?
- what is the purpose of removing the "get_instance()", is there any advantages by removing it ?
Thanks

It is because the architecture was changed.
There is no longer a CodeIgniter “superobject”, with framework component references magically injected as properties of your controller.

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