Not split or mesh on a large number of columns, it does not help. To manage such a grid will be hard, but still come across sites that it does not lie.
I made a generator flexbox grids on LESS: for each project I can generate meshes with different number of columns, hutterli different widths and different media breakpoints. Everything is customizable with 5 variables. By default my grid is trying to be like bootstraps 12 column, as the most familiar. But some of the chips I pulled from the grid, Zurb Foundation 6.
paulradzkov.com/flxgrid.css
Besides, flexbox is so flexible that speakers can divide the width automatically.
View example
paulradzkov.com/flxgrid.css/#auto-width-columns
You can mix columns with explicit width (fixed or percentage) and autovaruosade column. Ie website design is not required to be aligned strictly along vertical guides, as with float-nets.
Flexbox-grid can be adapted to almost any design, adding a little custom code.