Tom Jones kind of disappeared for a while, and did a “hip irony” thing with Prince’s “Kiss.”
Sparks had a string of hit songs and albums in the mid-70’s, were critically lauded, and were featured everywhere, from the Top of the Pops to Teeny Magazine covers. By the 80’s they were pretty much forgotten, even though they kept on putting out (mostly mediocre) albums.
Come 2002, and Sparks released an album that Record Collector later described as:
Ever since, Sparks has enjoyed hefty cult popularity, touring for packed out mid-sized venues all over Europe, and still putting out albums that do get noticed and do sell well.
Kylie Minogue. From one hit wonder with* I Should Be So Lucky* in 1987, back when she was a teen soap actress in Australia, to being pretty much remembered with slight embarrassment as an eighties thing, to her resurgence as an electropop diva in 2001 with hits like Can’t Get You Out Of My Head or Slow.
Huh. As a big Moodies fan myself, I’d regard “Your Wildest Dreams” pretty much the same way as you (and I) regard “The Voice.” They were really mostly a legacy band by the late 1980s. I caught them at Wolf Trap in 1987, IIRC, and sure, they played a good deal of their more recent stuff before intermission, but the real draw was the songs from their classic period that ended after Seventh Sojourn.
It was no where near the end of their run. Jerry died ten years after that song became a hit.
Aerosmith has been mentioned already. Alice Cooper had a rough go of it in the early 80’s with a couple of albums that only the diehards love. New wave kind of fucked him up, he sounded like he was struggling to fit in. (Plus fighting an alcohol problem.) When Metal got big, Alice found his new home.
In the Dark was the 12th out of 13 studio albums, not including the album with Bob Dylan. Jerry died in '95, eight years later.
Bob Dylan was popular in the early 1960’s folk scene, crashed his motorcycle and went into seclusion in 1966, then hit the comeback trail as a totally different type of musician in the 1970’s.
So not nearly at the end of their run.
Granted, but as far as I can tell they only had one Top Ten hit in the 1970s: their cover of Rock and Roll Music, which made it to #5. Near as I can tell, that was the only time they cracked the Top Ten from the start of ‘67 to the end of ‘87.
But then, in ‘88, they hit #1 with Kokomo.
Since this is the Straight Dope, and it is apparently de rigueur here to out-nitpick each other on trivial minutiae, “Touch Of Grey” was written by Garcia/Hunter back in the early 1980’s and first played live by the Grateful Dead in 1983, even though the hit album “In The Dark” that the song became the standout single on wasn’t released until Summer 1987.
Not a band, but Andrew Lloyd Webber’s first show Joseph went nowhere, he and Tim Rice hit it big with Jesus Christ Superstar, he and Alan Ayckborn’s show Jeeves totally flopped, he and Rice did well with Evita.
THEN he did CATS and became a theatre composer superstar.
Think that Neil Sedaka deserves a mention here.
If you think that one more studio album and touring with a declining Jerry Garcia who could barely sing by the 90’s didn’t mean they were near the end, there’s nothing I can say to you. ¯_(ツ)_/¯
Their resurgence came earlier than that. The delightfully-titled Gratuitous Sax & Senseless Violins came out in 1994, and got quite a bit of airplay as I remember.
I’m amazed that the only mention of David Bowie here is as the man who revived Mott The Hoople’s career. What about the man himself? Nothing between Space Oddity in 1969 and Starman in 1072 (not counting Oh! You Pretty Things as recorded by Peter Noone, which was a hit in the UK at least).
Roxy Music fit the pattern of successful, broke up, reformed, successful again.
But the one that I find most interesting is Ian Dury, because it was all on merit. After modest success in Kilburn and the Highroads, suddenly a star with Sex and Drugs and Rock and Roll et al, huge for a couple of years (77-79), lost his way completely. And then with Mr Love Pants (1998) an unexpected return to form and modest success cut short by illness and his untimely death. That’s Rock n Roll for you.
j
Cher’s carrer has been quite resilient. Sometimes she took a detour into television or movies. But her music has always remained popular.
She had a minor hit slump in the early eighties and then blew away the charts with If I Could Turn Back Time in 1989. Walking in Memphis in 95, and then Believe hit number 1 in 1998.
Do the Eagles count since they broke up for a while?
They didn’t break up. They just took a 14 year vacation. 
Three years isn’t that long, many artists have had such a hiatus. You could make a case for his late, 10-year silence (2003-2013), though.