[MariaDB developers] '_' in numeric literals [MDEV-33228]

I was going through this issue https://jira.mariadb.org/browse/MDEV-34228, and noticed that during parsing we check if '_' is present in a token , if it does it is parsed as an identifier. My question here is to follow a SQL2023 standard of '_' in numeric literals, how would one go distinguishing the difference between numeric literals and identifiers ? mariadb documentation says that a identifier cannot start with a number until its in backticks `{identifier}`. Rohan Gupta