The times I turned off personalized ads, were the times google ads went really wild. This was both for regular website ads as well as youtube ads. So many cosmetic product ads...
I had to turn it back on again because they were at least partly interesting compared to "SiCk oF aCnE?! sIcK of pImPleS??!"
Yeah, I have turned off personalized ads and I mostly get these inappropriate dating ads. I guess it's their way of annoying me into enabling personalization.