There's no requirement for a born-1995 codebase to still build on a 1995 system in 2023.
I work on a born-1995 codebase. We started requiring an ISO C11 plus GNU extensions¹ several years ago and are actively removing "compatibility" checks and kludges that are outdated.
[¹ to be fair - not needing to support Windows is a godsend for any C project.]
