I wanted to get my bitcoin address on Kucoin recently and I saw bitcoin lightning. You can also see it yourself:
I have not seen anyone that posted about it on this forum. I have four exchanges that uses lightning network for payment. The fee is still cheap and better than converting to an altcoin and convert back to bitcoin.
Other exchanges that I know that has lightning network for bitcoin payment are Binance, OKX, BitMart and now Kucoin.