Perhaps I missed something, but I wonder why WP didn't just include ACF functionality in WP Core from the very beginning?
Why fight in public when you can just commoditize your dependant competitor?
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Why fight in public when you can just commoditize your dependant competitor?
Doing as you said is much smarter, but maybe takes a bit longer. My guess is Matt was reaching for some way to "hit them back" quickly.
It sounds like a reasonable philosophy until you see just how many basic CMS features it's missing and subsequently how many sites are running 20+ poorly-coded plugins that spam the dashboard notifications and have numerous PHP vulnerabilities.