It baffles me when people use flex layout when it's clearly visually a grid layout. Nothing here is flexing with varying element sizes and auto-fill-wrap-break of items.
A colleague of mine prefers flex too. But to me, grid is so much more intuitive and simple.
(though I'm usually only using it to display some status just for me and not for external consumption; the UI side can have a JSON if it ever comes to that).
I used to be a full-stack dev, but I've been pure backend for so long now, everything I knew is outdated or deprecated.