Perl and Python are the only two examples of this to my knowledge: most open source languages do fine introducing breaking changes in major versions.
The question is why Perl and Python had such problems while for example NodeJS, PHP (comparable webserver scripting languages) have had no such issues.
I wonder is it anything to do with the areas they're used in (Python & Perl are popular local/cli scripting languages in addition to web—has Bash had similar version woes?), or is it purely that the changes they made were more significantly breaking than others'? That's probably true of Perl6/Raku at least.