Is autoloading still active? What are the limitations?

Trying to use the bedrock autoloader. Followed the instructions from here, which did succeed in adding plugins to mu-plugins directory. But bedrock-autoloader.php doesn’t seem to be running (or at least, I’m getting a lot of activation errors that I thought it was supposed to fix).

It could be that there are some limitations on the types of plugins that will work with the bedrock autoloader and I just don’t understand what those are. In which case, does anyone know?

It’s also possible that it’s simply not active anymore. Looking at the commits from when the autoloader was added, it seems to be dependent on the “autoload” and “scripts” sections of composer.json, which have since been removed. Does this mean the autoloader is also effectively defunct or is there an updated way of using it that I haven’t found yet?

And of course, it’s also possible that it’s neither of these and I just have no idea what I’m doing.