i'm afraid you're underestimating -3 ad/-50 hp nerf Sir
i'm afraid you do not realise what -3 ad can do, like slowing clears, making 1v1 a bit worse, reducing Sheen damage, sterak bonus AD, making last hitting more difficult, reducing sustain via lifesteal
i'm afraid you do not realise that -50 hp will make you dying WAY MORE TIME than you do
Everyone here recall the amount of time they survived with 50 hp a gank or a burst or anything, WELL THEN why don't you realise that with -50 hp you would be dead? and it's not even 50 hp, it's like 80 or 90 with a base of 40 mr and 30 armor
base stats nerfs/buffs are probably the highest amount of changes done in dota2, and it contributes so much to balance the game