IIRC Perl 6 wanted to expand or morph into something better, spent a ton of time on it, and the community in general rejected it hard.
So now we have this dangling language that's shunned by its own community, regardless of its merits. Weird place to be in.
Well Raku is not shunned by the very warm and welcoming Raku Community … https://raku.org/community
I think Perl was a lot further away than Python was from anything that would have allowed "trading some backward compatibility for some structure".
This was a clear case of a language collapsing under the weight of its own poor decisions and lack of coherent design. Could it have been kept on life support with a series of incremental improvements? Probably, but things wouldn't have gotten materially better for its users, and it would have bled users anyway as the industry left it behind.