Wet is ~40-50% reduction in traction on asphalt, and it's even worse for paint. That seems pretty serious. (Of course, surface oils can be even worse.)
Typically stopping traction is only mildly worse on wet pavement, but lateral traction takes a pretty big hit. It's a serious loss in any case, but the limits for good tires on dry pavement are so high that even at 50% of that you are totally fine if you just drive normal. With modern tires if you're driving more than like 3/10 the ability of the car you're probably driving like an asshat.
Typically stopping traction is only mildly worse on wet pavement, but lateral traction takes a pretty big hit. It's a serious loss in any case, but the limits for good tires on dry pavement are so high that even at 50% of that you are totally fine if you just drive normal. With modern tires if you're driving more than like 3/10 the ability of the car you're probably driving like an asshat.