coinmarketcap/coingecko are generally not very reliable for evaluating the stability of stablecoin pegs
most liquidity tends to aggregate on dexes like Curve, which is also where you could have seen the whole LUNA/UST debacle play out in real time as large actors swapped out of UST into USDC/USDT/DAI
the 'fee per fiat withdrawal' is 'The greater of $1,000 or 0.1%'
so it would theoretically make sense for the peg to be 0.1% off as there is no more profit from redemptions at that level.