Both GNOME and Plasma have their own tools for working with Bluetooth, but desktops like XFCE, MATE, and Cinnamon all use the same common set of tools, making working with Bluetooth speakers across these desktops super simple.
I use Bluetooth on Ubuntu Mate. What I have found is it can be very easy to a pain depending on the hardware you are trying to connect. I have a HMX Jam speaker, a pair of outdoor rock patio speakers and personal headphones. My Jam speaker connects easily every time, my rock speakers may take a couple of times to connect, and my headphones are a pain which always take multiple tries and I sometimes have to delete and completely start over to get connected.