The Moodle Coding Style (MCS) states:

Class names should always be lower-case English words, separated by underscores

PSR-12 states:

PascalCase where the first letter of each word is capitalized including the very first letter.

Required decision: Keep the MCS naming convention or adopt the PSR-12 recommendation?

MCS: https://moodledev.io/general/development/policies/codingstyle#classes 

PSR-12: https://www.php-fig.org/psr/psr-12/#21-basic-coding-standard