Then yeah CSS grid is not right for that project. But not everyone is in that camp - and some are a bit of both. We have clients like yours and then many others that don't even need IE11 based on their stats. The money saved because we can use more efficient tech like CSS grid mean more time to add features!

(All our websites work in IE11 - they're just allowed to be "visually different from the approved designs" - it's a pretty good compromise for many clients!)