Yes quite some time ago its limit was $2000 USDT and $2000 BUSD and interest was 10% APR but recently binance has reduced it to $1000 and interest is only 8% so if one is intending to stake more, then binance Won't work much for him.
But at least he can feel safe risking his USDT on Binance. Moreover, Binance is one of the big exchanges and already has a reputation among other exchanges. And with that result, he would benefit even if there was a reduction to the limit. If I were him, I would choose Binance to stake my USDT because it is a good passive income to try. But that's just a suggestion and he has to figure out what's good for him.
He will able to stake only 1000 USDT and 1000 BUSD which is much less amount . yes , he can stake safely his USDT on Binance and he can redeem his usdt any time instantly from Binance if he want. and binance will give him profit every day according his amount & Staking percentage . it is really a good feature .