1) A video about IE11 & CSS Grid:
2) A 7-part series on writing CSS that works all the time: youtube.com/playlist?list=…
No, no no.... you decide for each little bit of layout...
Each decision is independent of the others. Separate.
Sometimes Grid is the right tool. Many times it's not. Browser support is just one of many considerations.
IE11 dying will NOT change this process of thinking through robustness. You still need to do this — to consider what can go wrong.
Those people are holding you back in your career. They don't know. And they are hurting you.