I'm not sure anyone can with a straight face claim a "jungle clear speed nerf" matters when at the earliest it could take effect is level 8, for -5 damage.
By the time Lee Sin has E maxed, he is level 13 and has enough AD that -20 damage is irrelevant to clearing (as if a level 13 jungler cares about clear speed...). But more realistically Lee is maxing E last, so this nerf means at level 14 Lee Sin is now missing a whole 5 damage on his clears, while casually throwing out 700+ damage Q nukes to monsters.
Or calling the W change a 'nerf'. It's massively better until level 13, where Lee Sin now gets -1% omnivamp. The early game jungler getting a whopping +5% omnivamp levels 2-7 far outstrips the 'nerf' of level 13 Lee healing 20 less health per 2k damage dealt.
Most Lee Sin jungles max W 2nd.
For ~75% of Lee Sin players this is a 5 damage nerf at level 14.