Splitting responsibilities between controller and model

In my opinion, the Entity is the most opinionated part of CI4.

It is designed quite differently from plain PHP objects and should be considered carefully before deciding whether to use it.
Use it only if you think the features are necessary and quite useful.

Also, if processing speed is important, you should benchmark and make your decision, as Entity will slow down processing.
In PHP, objects cost more than arrays and are much slower when using magic methods.
Therefore, using Entity may result in a significant performance loss.

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