Mojo Nixon also had a song called “Debbie Gibson Is Pregnant (With My Two-Headed Love Child),” which features Winona Ryder in the video as the titular Gibson.
REM in Man In The Moon sing about comedian Andy Kaufman who is ‘goofing on Elvis.’
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Wheatus ‘listening to Iron Maiden, maybe’ in Teenage Dirtbag
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Another Elvis song is “Black Velvet” by Alannah Myles
There’s “Don’t Rock the Jukebox” about George Jones
And “Johnny’s Cash and Charley’s Pride” which references many country singers
Bowling For Soup in 1985 mention in the lyrics:
Whitesnake
Bruce Springsteen
Madonna
Nirvana
U2
Blondie
Wham
Limp Bizkit
Duran Duran
Van Halen
** Duran** (for some reason Discourse doesn’t like ‘Duran Duran’ in bold)
Ozzy
Plus the video includes some further visual references to Robert Palmer and George Michael
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Bowling For Soup and The Girl All The Bad Guys Want mentions Godsmack and Agent Orange
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Joan Baez wrote Diamonds and Rust about her relationship with Bob Dylan. I’ve always liked the Judas Priest (who took their name from a Bob Dylan song) version
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You missed one:
While it’s arguably not actually about The Replacements, I get a kick out of:
Smoke on the Water by Deep Purple references Frank Zappa and the Mamas (Mothers of Invention.) Here is a charity version of the song featuring a vast array of well known rock musicians
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You’re So Vain, by Carly Simon 
Maroon 5 - Moves Like Jagger
Crosby, Stills & Nash - Suite: Judy Blue Eyes (about Judy Collins)
Lady Stardust is believed to be a song about Marc Bolan.
“Natürlich hat er mir erzählt wie scheußlich alles ist….”
I listened to that album every morning on the train to work for a couple of months, and still love it.
The Dandy Warhols song “Not if You Were the Last Junkie on Earth”, famous for the line “I never thought you’d be a junkie because heroin is so passé”, was dedicated to the Brian Jonestown Massacre.
The Brian Jonestown Massacre responded with “Not if You Were the Last Dandy on Earth”
Eric Burdon’s Monterey mentions Ravi Shankar, The Who, Hugh Masakela, the Grateful Dead, Jimi Hendrix, and Brian (“Prince”) Jones.
Songs about Brian Wilson:
Rocket by Def Leppard references various artists and famous songs with the lyrics
Jack Flash
Rocket Man
Sergeant Pepper and the Band
Ziggy
Benny and the Jets
Jet Black (from The Stranglers)
Johnny B (Goode)
Jean Genie
Killer Queen
Dizzy, Lizzy (presumably Thin Lizzy)
Major Tom
The video contains further artist references (including, unfortunately, Gary Glitter who is now a convicted child sex offender. Although that wasn’t widely known when the video was made.)
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This is stretching the premise a little, but this jazzy Pete Townshend interlude was dedicated to Barney Kessel
Ben Folds did a “dis track” about his former pals Fleming & John (a band) called Brainwascht.
There are tons of dis tracks in hip hop, with artists writing about other artists. It might be futile to try to mention them here.
Missy Elliott did “Can You Hear Me” about missing R&B star Aaliyah.
And of course, Diddy did “I’ll Be Missing You” about Biggie Smalls.