I don't know of any article links, but I can look for some.
I always assumed that the reason no more episodes were made was due to an ever changing market. He-Man and the MOTU spawned a whole copycat generation of cartoons and toylines. Unfortunately the figures and the cartoons became a victim of their own success.
Filmation even tried to pitch a new MOTU based show (about He-Man and Teela's child), but I think Mattel saw the writing on the wall and had moved on.
Also Mattel knew there was enough episodes of He-Man and She-Ra to help sell their toys that they wouldn't need to commission any more. When sales started to dwindle for the figures they scrapped their plans for the new wave and the rest is history.
I think part of the problem is Mattel has never been one of those companies that rolls with the punches. You would think that as MOTU dwindled an in-house team would start to work on the next big thing, but Mattel was licensing Bravestarr (15 million worth of figures were shipped in 1986 and Mattel bought 50% of all commercial time during the show) instead of coming up and supporting their own IP. They also paid to release MUSCLE - again forsaking the creation and marketing of their own IP. I guess with Food Fighters and Computer Warriors waiting in the wings they knew they needed to look outside of their own four walls for creative ideas.