This is exactly what we were *nudging* for. It's not a movement against, just a growing process. The SVN has served it's purpose but now a more decentralized approach works since the tools and dev approach have changed.

I created the "pure-data" GH group as an umbrella for this kind of development, so we could think about moving generally useful & actively support externals there. Then anyone can do a PR or be given externals development access via GH groups, etc without worrying about "stepping on anyones toes" or being stuck with something on their personal account. Original authors, of course, are free to take over their own projects and move them if they want, but there are definitely cases of externals which have become more community developed.

A centralized SVN repository with all externals in it seems like it has
been a point of friction in the Pd development ecosystem.

You could set up your stuff in Github repositories, and if somebody
wants to continue to use SVN and also wants your fixes then they can
figure out how to merge them back. I would make contact with people who
are doing packaging of the externals for distributions and tell them
that you have versions of those externals with newer modifications and
they can decide whether to continue to use the SVN version or your newer
versions with changes.

Hm, maybe this is too aggressive a strategy, I don't know.

In any case, I don't think there is anything inherently wrong with
forking code and putting it in a Github repository and making
improvements. That's basically the whole point of FLOSS. Then if people
want to use your new versions, great.

--
Dan Wilcox