The OP is focused on the point totals of all-time great offensive forwards i.e. those who normally receive the most attention for league's best player. Subjective awards for non-forwards is not relevant to the OP.
Can you provide any concrete evidence that the pack of elite scorers (the Top 20/50) was "weaker" from '96/97 to '03/04?
I am presuming you do not see Jagr's peak as being as being as good as his relative dominance would indicate.
Am I correct?
Yes, Jagr's dominance in scoring was in part because his competition was cut down by injuries. Credit to him for being durable, but his scoring dominance would have been very different if Mario, Forsberg, Sakic, Kariya, Lindros, Palffy, Selanne, and Bure were playing full seasons and unaffected by major injuries.
Forwards who averaged at least a point per game from 96-97 to 02-03, and played in 96-97 and 02-03.
Regular season stats from 96-97 to 02-03
Mario Lemieux: 210 of 574 GP (37%)
Jaromir Jagr: 509 of 574 GP (89%)
Peter Forsberg: 412 of 574 GP (72%)
Joe Sakic: 484 of 574 GP (84%)
Paul Kariya: 477 of 574 GP(83%)
Eric Lindros: 394 of 574 GP (69%)
Ziggy Palffy: 488 of 574 GP (85%)
Teemu Selanne: 542 of 574 GP (94%)
Pavel Bure: 419 of 574 GP (73%)
Mike Modano: 524 of 574 GP (91%)
Pavol Demitra: 426 of 574 GP (74%)
8 of 11 played less than 85% of the available games, and 5 of 11 played less than 75% of available games.
And 5 of these 11 had major injuries that cut them down early in their prime so they couldn't maintain their peak level of play even when on the ice. Lemieux's back, Kariya and Lindros's concussions, Bure and Selanne's knee injuries.
Jagr should have had much better competition for his scoring finishes if not for these injuries.
Also, very few young players were competing for top scoring finishes during 96-97 to 02-03 compared to the previous years or the following years. This shows the weakness of the talent entering the league in those years.
From 92-93 through 95-96, top 10 scorers - 17 of the 40 spots (43%) went to players under 25. (Turgeon, Selanne, Mogilny, Recchi, Fedorov, Roenick, Bure, Shanahan, Jagr, Lindros, Zhamnov, Renberg, Forsberg, Kariya).
From 96-97 through 02-03, top 10 scorers - 11 of the 70 spots (16%) went to players under 25. (Jagr, Kariya, Palffy, Forsberg, Allison, Demitra, Elias, Iginla, Thornton, Heatley).
99-00 through 02-03 was particularly lacking in young scorers, with only 4 of 40 top 10 spots (10%) claimed by players under 25. (Elias, Iginla, Thornton, Heatley).
And then from 03-04 to 09-10, 24 of 60 top 10 scoring spots (40%) went to players under 25. (Kovalchuk, Hossa, Tanguay, Ovechkin, Heatley, Crosby, Staal, Malkin, Spezza, Parise, Getzlaf, Backstrom, Stamkos, Kane).
It's pretty clear that the weak draft classes of the mid to late 90s caused the late 90s/early 00s to have weaker competition for top scorers. Especially the early 00s.