In reply to Anh Tran.

Regular users won't know how to build a block (and never will). I'm not a fan of this solution (nor of page builders, tbh) but I understand its use.

Gutenberg has this paradoxical thing of being developed to make life easier for regular users to customize their pages but, at the same time, it alienates a great part of WordPress users that depend on its flexibility, plasticity and easy extendibility.