The blocked resources in question? Automatic security and features updates and plugin/theme repository access. Matt Mullenweg reasserted his claim that this was a trademark issue. In tandem, WordPress.org updated its Trademark Policy page to forbid WP Engine specifically (way after the Cease & Desist): from “you are free to use [‘WP’] n any way you see fit” to a diatribe:
The abbreviation “WP” is not covered by the WordPress trademarks, but please don’t use it in a way that confuses people. For example, many people think WP Engine is “WordPress Engine” and officially associated with WordPress, which it’s not. They have never once even donated to the WordPress Foundation, despite making billions of revenue on top of WordPress.
https://techcrunch.com/2024/09/26/wordpress-vs-wp-engine-drama-explained attempts to provide a full chronology so far.
Wix and Squarespace managed to be even worse options anyway.
Anyway who cares what the client thinks, they don’t know anything that’s why they’re hiring a professional. The professional thing to do would be to convince them of the advantages of one of the listed options.
Anytime I’ve ever had to deal with WordPress I’ve always run up against the fact that it has limitations that the client doesn’t understand, and then at some point you end up redesigning it custom anyway. May as well save time and start out custom.