As a developer I want a PSR-3 compatible Logging API
PSR-3 aims to set a standard for Logging in PHP.
Adapting this standard for the Logging API on TYPO3 would allow developers to replace the core Logging implementation with any other PSR-3 compatible logger (given the necessary dependency injection is in place).
It also would ease the understanding how to log in TYPO3.
#1 Updated by Ernesto Baschny about 5 years ago
In my understanding the major benefit of implementing a PSR-3 compatible interface in TYPO3 is not to "allow developers to replace the core Logging implementation", but to allow third party modules/packages which log to PSR-3 to be integrated into TYPO3 without modification (simply injecting the PSR-3 Logging Interface from TYPO3 into it).
From the Standard:
"The main goal is to allow libraries to receive a Psr\Log\LoggerInterface object and write logs to it in a simple and universal way."
The easiest way would be to provide an adapter which implements this interface and under the hood uses the (more sophisticated) TYPO3 API. TYPO3 Core could still use TYPO3's own API (which provides more flexibility).