It seems to apply mostly to crypto's that are worth a few dollars or less each.
It wouldn't be so bad if they would just collect the fee in BTC or ETH, instead of the token you trade! No idea why they do that.. but the subreddit is full of complaints about how people have collected lots of untradeable 'dust'. It can add up if you have a bunch of them , and each is worth a few dollars.

There are some workarounds.. the BNB markets do allow for fractional trades. Maybe they do this on purpose to stimulate BNB trading? However on the BNB markets a new problem is introduced... you have to trade atleast 1 BNB worth of tokens minimum. So To get rid of 0.98 RDN you first need to buy 2.02 RDN and then sell 3 RDN, in order to stay above the minimum trade amount.

I hope they fix this eventually! No sense in withdrawing my 0.98 RDN to try and sell it elsewhere if the withdraw fee is like 0.6 RDN..
This system works this way either by mistake, or they are very clever people