LB is definitely stronger than Yumi.
However, there is no opinion that Britain is more OP than Japan.
And how do other civs without LB deal with Yumi?
A simple comparison of units is meaningless unless you are using only one unit.
I wrote not only Yumi, I also wrote about Ashigaru and the shrine.
Besides that, I plan to experiment with other Japanese OP units and write a thread.