There has never been protection removed from the Free version.
Regarding the memory usage, I don’t think the new versions use any more memory than the older ones (even though it might seem to if you look at the Task Manager, but the numbers mean something else than generally expected).
The self-defense has been there since… I don’t know, avast! 4.x. It’s an important layer of defense against malware. But you can disable it in the Troubleshooting options, if you feel you don’t need it.
Similarly, the sounds have also always been there (and enabled by default), i.e. no change here either.