Just awful. I use a plugin that is (yes) it's not maintained anymore and no longer works. I needed to roll back to 5.4 to get my site working again. I can't imagine the nightmare I would have had if I ran a major website with thousands of users. I'll have to fix the plugin myself because it's absolutely crucial to my site. It's pretty bad that an auto update broke my site though.

This is after the last major release of WordPress where wordpress started automatically creating additional very large size images. Did this without warning and even though there was supposedly a way to stop it. you couldn't. The stop failed to work and still isn't resolved. It was a serious problem for my site in more ways than one.

All of this really makes me second guess my love for WordPress. I will be much more hesitant to use this as a platform for major websites.