It's a bit of a poisoned chalice.
Because you see, a few months ago, they stopped Bitcoin payment support on their Coinbase Commerce payment gateway service (why they would do that still baffles me). But now they are supporting Lightning Network for their customers, so that means they would hopefully have to add back Bitcoin payments but for LN, because othewise it makes no sense to have a payment processor whose options for payment settlement are Ethereum and a bunch of shitcoins.
There is always a poisoned chalice with these big exchanges, they have plans for the next 10 years as well. I was not aware of the payment gateway services, thanks for bringing it to light. But I don't think it's necessary for them to allow it again I mean this service is for e-commerce sites, so they could integrate coinbase APIs directly for easy integration of payments,
But if coinbase has allowed LN that can also mean, they have allowed it for only withdrawals and deposits on there exchange only. Anyone with LN set up from one wallet can send or receive funds on the exchange directly. But your point worth to be noted, let's see what will they decide. I don't think they will bring that feature back.