[JeanMarcS]

I think it depends of if you need trafic from those browser or not. Because if you do, you'll have to maintain several version, or increase your time on working on it to do gracefull degradation (which is of course a good way to do, but more expensive)

[_betty_]

but that's kind of the beauty of css grid, the gracefull fallback is basically mobile view which you already put effort into.