Can someone please explain why the 6% max health damage (Wolverine) is supposedly better for tanks vs squishies? Two part question with (most likely) bad math included.

6% of 100 is 6 damage and 6% of 1000 is 60 damage, and in each scenario it would take 17 hits (of just the percent) to break past the max health. So, with this in mind, why do people say Wolverine is good for tanks and weak for squishies?

If the damage output is the same amount of hits, couldn't he be used to target squishies and shred them the same way as people say he shreds tanks?

Or is it simply the fact that it is IDEAL for him to go after tanks because of the fact that he shreds them so easily when compared to other DPS characters?
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Now, this is the part where I feel like I'm doing something completely backwards or being super blind to the math:
Flat damage in this case FAVORS targeting squishies, because his basic attack does 15 flat damage. His attack would do 21 damage per hit (6 from example above) making a 100 max health character only need 5 hits to die. A tank with 1000 health would make his attacks 75 per hit (60 from above example and 15 flat) making the 1000 max health character need 14 hits to die.

What am I missing here? I feel like I'm overlooking something very obvious.