You can also make an optional dependency on Data::Dump::Streamer rather easily. Using MakeMaker, you'd only document that the user installing Data::Dump::Streamer would allow blessed regexes to be used. Using Module::Build, I think the optional dependency could be declared such that the plethora of automated installation tools can decide to ask the user if they want to install it.

I don't know what did or didn't change in 5.010, but I'd jump to the same conclusion as you for the same reasons.