Already in the very early millennium, jokes like “Perl is an explosion in an ASCII factory” were going around the computer-nerd community, while several publishers were putting out affordable and fun and engaging books to learn Python. No surprise that Perl quickly declined in popularity for scripting. It has been amusing to watch the continual waves of reawakened interest in awk, while Perl seems to remain perennially marginalized now.

The value proposition for AWK is very different from Perl. AWK is a tiny language that can be learned quickly, and it's ubiquitous: a hard requirement for even the most bare-bones POSIX environment. AWK is on your machine already; Perl may not be. If you have to install Perl, you could just as easily install any one of hundreds of alternative scripting languages.

AWK scripts don't have any kind of dependency management features, so they naturally lend themselves toward being freestanding and self-contained. Perl, on the other hand, has a massive package ecosystem with transitive dependencies and widely varied quality and design aesthetic, amplified by the baroque design of the language. AWK is as close as a language can be to immune to dependency hell.

When Perl was new, perhaps many people saw it as "a better AWK", but I suspect most of the newcomers to AWK today don't see it in relation to Perl at all.