I honestly don't see what's so great about that 1991 chart, TBH. You have a handful of generic and random rock acts (Telsa, Bad Company, Styx, Sting...) Bubblegum kiddie R&B/Hip Hop (Tracie Spencer, Tevin Campbell, Another Badd Creation)...Dentist Office Music (Chris Issak, Gloria Estefan, Surface, Wilson Phillips, Celine, Whitney, Mariah, Oleta Adams)...corny pop rap (C&C Music Factory, Gerardo)...fluff (Madonna)...one hit wonders (Tara Kemp, Timmy T, Londonbeat, Enigma)...Playboy Hip Hop (LL Cool J.)

Not much has changed.

Bubblegum kiddie R&B/Hip Hop: Migos
Dentist office music: Ed Sheeran, Bruno
Fluff: Taylor/Zayn, The Chainsmokers
Playboy Hip Hop: Future, Drake (I know they're not on the singles list, but they're on the scene)

TGJ only posted the current top 5, but I'm sure the rest of the top 25 has what can be called today's equivalent to the rest of 1991's top 25. The names and faces may have changed, but you can pretty much get the same thing now as back then.