My wash-n-go did not result in tangles or matting. My hair is a 4a/4b mix with the emphasis on the 4b.

I finger detangled thoroughly for this wash-n-go because I noticed that when I use a comb, it breaks up my natural coil pattern and creates mega frizz.

In this pic, my hair is still pretty wet and the product that I put in hadn't absorbed/evaporated yet. Admittedly when it completely dried, the coils were still defined but were much tighter. Still frizz was no more or less than when it was soaking wet and when I re-wet my hair to style again, like I said, there were no massive tangles or matting. Mainly (I think) because I took the time to thoroughly (and I mean thoroughly) finger detangle.

Though I don't wear my hair in wash-n-go's often, I would have to say to the OP's inquiry, that the answer is "yes for some 4b's".
Attached Images
Me Fascina El Pelo

Low Porosity; Medium Strands; Dense