You just limit yourself. I have built database-style wordpress sites with custom taxonomies/types using just my own glue code, theme templates and Advanced Cust

You just limit yourself. I have built database-style wordpress sites with custom taxonomies/types using just my own glue code, theme templates and Advanced Custom Fields (and ACF is just there for the backend experience mostly). It's also obviously not the best choice for everything, but some of these sites I built 10 years ago and they're still going without major issues.