Web would be a better place without UI animations.
UI animations and needless "glitz" is inconsiderate of low-vision users, users who might have poor technical skills and who rely on UI consistency to accomplish tasks, users with low-spec hardware, users who are forced to use remote framebuffer protocols over low bandwidth connections, and of the environment (by way of increased processing power and electricity required).
$instance_of_some_witty_template
The trend is there because the majority of humans obviously enjoys moving pixels. If you don't you just need to accept it.