Jordan referred Kobe to Grover in the summer of 2007 because Kobe told him his knees were in extreme pain. Tim Grover talks about it here:
Oddly enough both Kobe (interview on youtube asking him about #8 vs #24) and Jordan (Kobe relating a story about Jordan talking about 03 Kobe vs 91 Jordan) thought 2003 Kobe was the peak version of Kobe (24 years old)
Ironically these problems all started when he bulked up in 2003 and 2005. I noticed the same thing happened to McGrady after bulking up when he went to Houston.
This is Kobe talking about the 2006 season when he averaged 35 ppg, but was clearly not performing at the same level of athleticism of prior seasons (just look at his dunks that season). 2004 even more of an exception when he didn't have a chance to rehab from knee and shoulder surgeries the summer before:
It was common knowledge that Bryant's knee bothered him last season, but apparently more than he let on.
"It took me 45 minutes to warm up for practice and games. It was crazy," he recalled. "It was very sore, you just played around it. I couldn't attack, put pressure on the defense the way I wanted to."
https://www.espn.com/nba/news/story?id=2597017
This is from the 2011 season, talking about the 2010 playoffs:
How did Kobe propose to pull that off, a Lakers’ legionnaire wondered, ‘when he hasn’t practiced the whole season (something no member of LA’s press has called him out on)?” Is that true, I asked Kobe? ‘Yeah.’ Why? ‘Because I have very little cartilage under my right knee cap, it’s almost bone on bone.’
Bryant has undergone three operations on that same knee, one this past offseason, after having it drained several times during last year’s playoffs. ”Until I got it drained the first time during the opening round against the Thunder I could not bend that knee at all,’ he revealed.
https://www.slamonline.com/archives/kobe-bryants-right-knee-is-almost-bone-on-bone/
https://www.nbcsports.com/nba/news/kobe-admits-his-knee-is-nearly-bone-on-bone
Especially when you look at Kobe from 2007 on, he was really a shell of what he was athletically in 2003. 2003 Kobe (24 years old) and prior was blowing by guys like Vince Carter and T-Mac like they weren't there.
This is 24 year old Kobe vs 24/25 year old Jordan (Kobe is probably about 20-25 lbs heavier. He actually seemed to lose some speed and leaping from prior seasons):
Similar discussion here:
https://www.reddit.com/r/nba/comments/8flo86/serioushow_did_kobes_2003_offseason_knee_surgery/
https://www.reddit.com/r/nba/comments/1fhzrqq/highlight_preknee_surgery_kobe_displays_his_full/