You could say that, yes, except that until recently, Apache's support for FastCGI was crap. The technology was essentially abandoned for 5 years, until they picked it up again a few months ago.

Why? Because they can feel the pressure, from Lighttpd, for one.

Other platforms, like Zope, Ruby On Rails, and even PHP, apparently prefer to use FastCGI or similar technologies to an embedded interpreter. I think it would be a better alternative to mod_perl, too, because, well, if each website has its own persistent Perl environment (which I can envision to actually be much like mod_perl), they can't crash each other. The scripts interpeter would be running independently of the webserver, so it can't touch the internals of the webserver either.

As a whole, this looks to me like it would be a lot like the "mod_perl light" the OP was dreaming out loud about.