1. You can use virtually any language to write clean code
Not sure if I agree with this, though it may well be true. I just know there are some things like Brainfuck where it's designed to be impossible. I realize that language is created specifically for the purpose of making a coder say "WTF", but perhaps there are other languages that are not designed to be so that are really nearly impossible to write good code in.
2. Perl lends itself to unreadable code
If you stick to Modern Perl you still might end up with things like `wantarray` in your code so I guess this is kind of true. You need to be judicious in your use of code.
Some languages lend themselves more easily to writing clean code, like I feel about Go or if you hate the Go type system, Ruby. Even in Ruby I feel like metaprogramming is ripe for misuse.
It's a tough thing to talk about. I don't feel like I wholeheartedly disagree with your sentiment which seems to be "some languages lend themselves to bad code" and subsequently that Perl lends itself to bad code but there is plenty of ambiguity in these thoughts.