Sure, that's also how PHP started. Thing is, with Perl and PHP, before mod_perl and mod_php, your script needed to be parsed for every single uncached request,

Sure, that's also how PHP started. Thing is, with Perl and PHP, before mod_perl and mod_php, your script needed to be parsed for every single uncached request, easily dominating everything else, like URL parsing and process creation time. Hence natively compiled CGIs weren't such a bad idea. They're even used today a lot, with Apache/CGI uptimes measured in decades since neither Apache nor CGI binary updates require planned downtime on Unix. Its ultra-robustness is one of the reasons the concept of FaaS has become fashionable again.