There are a lot of different tellings of this story; here’s one: https://www.thoughtco.com/when-mtv-first-aired-black-videos-...

Here is the relevant excerpt from the link provided by another user. "Scant" is read by me to mean 'yes there were in fact videos, just not in the proportion to what should have been" in direct response to "they would not play videos"

There is no room for 'sides to the story'. It was a statement made and countered by this source. We can take issue with the source if you like, but I looked them up and didn't see anything partisan about them.

When MTV debuted on Aug. 1, 1981, at least one black face on the network was a mainstay. It belonged to J.J. Jackson, the sole African American on MTV's roster of video jockeys, or VJs as they became known.

Despite Jackson’s presence on MTV through 1986, the network faced allegations of racism for giving scant airtime to videos featuring people of color. MTV executives have denied that racism was at the root of the network’s “blackout,” saying that black artists received little airplay because their music didn’t fit the channel’s rock-based format.

“MTV was originally designed to be a rock music channel,” said Buzz Brindle, MTV’s former director of music programming, to Jet magazine in 2006. “It was difficult for MTV to find African American artists whose music fit the channel’s format that leaned toward rock at the outset.”

With so few black rockers, adding African Americans to MTV’s roster proved difficult, according to the network’s co-founder Les Garland, whom Jet also interviewed.

“We had nothing to pick from,” Garland explained. “Fifty percent of my time was spent in the early days of MTV convincing artists to make music videos and convincing record labels to put up money to make those videos…”

Michael Jackson's Thriller video was a huge force in bringing MTV to mass audiences.