It comes across as weird to me that it's so hard to get an actual NetMD deck which isn't portable since my mental image is that I make cassette tapes with a deck plugged into my stereo/computer and play them back on a walkman or car deck. But yeah, at some point I just started recording MD's off my computer the same way I record cassettes.
I can only assume Sony thought that most people wouldn't keep a hifi deck near an early 00s desktop PC. And by the NetMD era, portable MP3 was the hot new thing so that got most of the attention. There were some cool Vaio PCs and laptops with NetMD drives built in that I would like to play with...
My main 2-channel system is a Denon AV Receiver with a burned out video board, two Panasonic speakers I got for 1/10 the original cost and a stack of obsolete audio sources (two tape decks and a minidisc player) next to a M4 Mac Mini with a USB audio out that has coax, optical and analog outs so I have all the bases covered. By far the computer is the most common playback source.
The PC is for me as well - I run a Lenovo ThinkCentre tiny through a Yamaha MD8 MiniDisc multi-track recorder which then goes into my Yamaha 5.1 receiver. The MD8 is used for karaoke, and the receiver uses Dolby ProLogic to make it surround.
For recording MDs I use a Sony MZ-N920 with Web MiniDisc Pro.