Upon returning to my Wordpress controlled content, I was amazed by the slowness; it was initally nice to get "help" to order the content but some gallery plugins were really painstakeingly buggy, suddenly stopped working. I changed photo plugin, but same thing happened after a while, the plugin suddenly couldn't find the third uploaded gallery... I now have to handle more content "by hand".
One big advantage are that you then really have to consider the technical architecture and think about tools to keep the site content in order. Using Wordpress leads to the developer getting detouched from the basic web technologies and having to learn Wordpress specific details, learn plugins that might at any moment become unsupported.
The web development feels much more interesting now that you can expect similar look and behavior over the common browsers. Microsoft are also finally giving up Internet Explorer as well as the Edge browser.
Only worry though is that Chrome have the dominant position. Firefox has greatly improved concerning speed, previously it was very "mono threaded"... The plugins for Firefox are still fantastic. No one wants a new web browser "monopoly", I think...