There might be, but as of a few years ago they were not mature and may not have captured the mindshare yet. Company I worked for actually used websocketpp because Boost ASIO implementation had some bug they couldn't work around, but then it was fixed and we dropped websocketpp.

I can say one the the nice thing about Boost network implementation (ASIO) is fairly mature asychronous framework using a variety of techniques. Also if you need HTTP or Websockets you can use Beast which is built on top of ASIO.

And if you're using one thing from Boost, its easy to just use everything else you need and that Boost provides to minimize dependencies.