Definitely Ethereum still but not for ERC20 tokens.

Eth gas fees were ($0.9187) and BTC gas fees were ($1.450) today. If you're comparing popularity as a payment method though, this just means BTC is still more widely used, hence more transaction fees. Payment processors like https://www.poof.io/ and https://cash.app/, Square, Coinbase... etc probably all have extremely high payment volume with Bitcoin.