Well, yes and no. Based on raw rankings, sure, but Kelly's VsX among defensemen is 147 over his best 7 years, and 117 over his best 12 (only 12 spent as a defenseman). Lidstrom's comparable numbers are 109 and 103.
Kelly is completely on another level offensively, probably ahead of anyone except Orr, Coffey and soon Karlsson.
Lidstrom relied heavily on the powerplay to get points, which is fine, being good on the powerplay is one thing to consider, (and I'm sure Kelly benefited from heavier PP usage too) but being a true catalyst to puck movement at even strength is also important, and it's all too easy to roll both together into one ball and make a judgement about how "good offensively" a defenseman is.
I did a quick look at their ES stats since Kell's are now available. His Es VsX scores among defensemen are:
78, 71, 130, 182, 172, 163, 133, 129, 119, 78, 83, 58 (7 year, 147, 12-year, 116) - surprisingly, almost identical to his VsX scores that include PP points. Did not expect to see this.
Lidstrom's scores are: 62, 41, 78, 63, 71, 84, 82, 92, 106, 90, 100, 97, 52, 94, 84, 121, 78, 84, 69, 50. This is all over the map. Surely he was a consistent even strength producer, but he was not often elite, at least not for the standards of this round. His 7-year score: 100. His 12-year score: 93. It's actually Lidstrom's numbers that get hurt the most by taking a look at even strength on its own.
Is this perhaps a really impressive score once you compare to other modern players? It doesn't look like it. Just going by the years I calculated, Leetch's 7-year score is 112 - and this excludes 1989, 1990 and 1991. Bourque's 7-year score is 88, based only on his age 30+ seasons. Gonchar is a 94. MacInnis is a 79 without his first 8 seasons. Niedermayer is a 94. Housley is an 86 without his first 9 seasons.
Lidstrom would be behind at least a half-dozen post-1980 defensemen as an even strength producer if I did this calculation for all seasons, while Kelly was clearly head and shoulders above his contemporaries.