Disadvantages

The language has a bad reputation because of the "write only" way code can be produced in it, but, to be honest, you can write obfuscated code in all languages, some make it more difficult (Assembly, Java), some make it less difficult (JavaScript, Perl).

Perl is easy to write, hard to write well. You will need a lot of experience to write good Perl code.

Perl isn't geared for User Interfaces. To this day I can't figure a simple way to create UI.

If you did years of Linux, bash, C, sed, awk, etc., for you Perl may seem intuitive. But if you came from Windows, and you don't have enough UNIX experience, a lot of the "intuitive" stuff probably looks totally insane. If you were forced to maintain such "write-only" code, you'd be probably angry.

Finally, using prefixes like $, @ and % on identifiers isn't a good way to express your type system. Sigils are coming from BASIC-like languages. Ideas that BASIC initiated in general aren't very good practices today.