It's not a couple. Only about a third of the 5* signed in the past 10 years were legit stars for LSU or in cfb at all.

Kevin Tolliver II (never panned out)
Donte Jackson (decent nickel at LSU, but has done much better in NFL)
Chidi Okeke (who?)
Michael Divinity (solid LB that played several years, but he wasn't a Perkins type game changer)
Rashard Lawrence (solid, but similar to Divinity above)
Kristian Fulton (Very good, but lost 2 years)
Jacoby Stevens (bounced around positions for several years until he had a good last season at safety)
K'Lavon Chaisson (solid playmaker for us)
Terrace Marshall (stud)
Ja'Marr Chase (stud)
Marcel Brooks (bust)
John Emery (didn't pan out)
Derek Stingley (good his freshman year then bailed out)
Kayshon Boutte (one good year, but was never the same after the knee injury)
Eli Ricks (head case)
Arik Gilbert (great freshman year and then bailed)
Maason Smith (jury is out...this upcoming year will determine his LSU legacy)
Harold Perkins (stud, even though House screwed up his sophomore season)
Da'Shawn Womack (jury still out, but I can't wait to see this guy get turned into the monster he could be.)
Lance Heard (looks like he will be a stud)

These are all the 5* as of the end of the recruiting cycles for 2015 - 2023 according to 247. There are only a handful of guys in this mix that were bonafide stars and there were several that were busts or only had 1 good year. The point being that championship teams are generally built of mostly 4* with a smattering of 5* and 3*. Usually your 3* are depth guys, but there are more than just a few that have had significant playing time and impact on their respective LSU teams (Mason Taylor, Ali Gaye, Cordale Flott, Charles Turner, Jaray Jenkins, Damien Lewis, Saahdiq Charles, Patrick Queen, Neil Farrell, Justin Jefferson, Lloyd Cushenberry, and Foster Moreau from the same 2015-2023 period).