I "manage" about 175+ WordPress websites. Gutenberg came too late, so many clients were already using "visual builders" and therefore couldn't easily switch to Gutenberg. On every single other site that wasn't using a visual builder plugin, we disabled Gutenberg as initially it caused issues with the existing themes and plugins (CSS/JS conflicts etc.)
Time has passed, and it's now better but with so many WordPress sites "in the wild" it will take a lot of time for the majority to switch over.
Time has passed, and it's now better but with so many WordPress sites "in the wild" it will take a lot of time for the majority to switch over.
The bigger issues recently are the changes within the WP core to how jQuery is handled (currently being phased in over 3 releases https://make.wordpress.org/support/2020/12/handling-potentia...).
The WordPress ecosystem is robust, wild and messy and it should stay that way IMHO.