It's Yul and yul optimize used by most of solidity developer now?

It’s Yul and yul optimize used by most of solidity developer now?
I am trying to understand how solidity compiler works.
I find that there are two path to generate evm bytecode.
the legacy compiler with opt and the YUL with yul opt.
So, is the use of Yul along with Yul optimization the mainstream approach for live contracts currently, or is it the traditional legacy optimization method?