"Am I missing something big here, or is this all safe to use in 2022?"

CSS Grid has been safe for use for a few years now (if you're supporting modern browsers).

https://caniuse.com/mdn-css_properties_display_grid

The problem is that popular frameworks like Bootstrap and Bulma still don't support CSS Grid (they use flexbox only for layout).

It's ironic that developers have rightly complained how cumbersome CSS layout has been in the past. Now we have CSS Grid - and yet developers still aren't using it.