Yes it is - but it requires you to install it by hand.
It also requires you to know which dependencies any given package pulls in.
What you call bloatware - the Qt apps - is part of the Qt tools which is used to build KDE - you cannot avoid them because they are dependencies of the tools.
Avahi is a network tool and the Network Manager depends on Avahi - unless you choose another way of managing your network - you cannot avoid it.
Htop is a console application to view and maintain running system processes much like the tasklist on Windows. It can be uninstalled but not recommended as it can turn out to be the tool you suddenly need to kill a runaway process.
The best way is to learn how to install by hand - then you will have the lean system you are looking for.
You can start here
Then add in the KDE desktop