Basically LXDE got rebranded into LXQt, though since DEs and WMs don't get obsolete fast, LXDE will continue to work for a long time. You can still pick LXDE in Debian if you prefer Gtk 2 for some reason.
It’s a bit more than a rebranding, being completely rebased on a different framework, and LXDE still gets some work, for example, LXTerminal has commits from September. [0]