As far as I know, it is popular in bioinformatics because of https://bioperl.org/ Universities use that often in their curriculum.
As the cost of sequencing keeps coming down, we sequence deeper, and the computational demand goes up. Plain-text is replaced with binary formats, and most of the heavy lifting is now done by compiled libraries. The benefits of Perl aren't really relevant anymore, and given the choice most of us simply prefer writing Python or R.