Does it matter whom you plagiarise from?

According to Bob Dylan, it does:

Journalist Mikal Gilmore asked Dylan what he thinks of the "controversy" over quotations in his songs, stemming from the works of other writers, including Japanese author Junichi Saga and poet Henry Timrod.

…

"Oh, yeah, in folk and jazz, quotation is a rich and enriching tradition," he responded. "That certainly is true. It's true for everybody, but me. There are different rules for me. And as far as Henry Timrod is concerned, have you even heard of him? Who's been reading him lately? And who's pushed him to the forefront?... And if you think it's so easy to quote him and it can help your work, do it yourself and see how far you can get. Wussies and pussies complain about that stuff. It's an old thing - it's part of the tradition. It goes way back."

But:

Meanwhile, Dylan, himself has been caught up in lawsuit involving use of his name. In 1994, he filed a trademark infringement lawsuit against Apple, asking for a court order to keep the computer giant from using his name. There are also reports that Dylan reached an out-of-court settlement in 1995 with Hootie & the Blowfish over the band's hit song "Only Wanna Be With You." Dylan reportedly claimed frontman Darius Rucker borrowed some of his lyrics in the track.

It sounds as though it’s okay for Bob Dylan to plagiarise from a nobody but it’s not okay to copy from Bob Dylan.

Here’s some old news:

In interviews promoting Amused to Death, Roger Waters, formerly of Pink Floyd, claimed that Lloyd Webber had plagiarised short chromatic riffs from the 1971 song "Echoes" for sections of The Phantom of the Opera, released in 1986; nevertheless, he decided not to file a lawsuit regarding the matter.[25] The songwriter Ray Repp made a similar claim about the same song, but insisted that Lloyd Webber stole the idea from him. Unlike Roger Waters, Ray Repp did decide to file a lawsuit, but the court eventually ruled in Lloyd Webber's favour.[26]