Going viral is not necessarily a profitable event for most businesses. Especially overnight virality.

I maintain a few WP sites for small businesses. Precisely none of them would benefit from the kind of traffic spike that would incur a $50k cloud scaling bill.

If you’re running an online store, maybe, but by now almost all of those businesses are on Shopify where that isn’t an issue. 99% of all the businesses with WP installs I’ve touched would only be harmed by autoscaling instead of just choking on the traffic. Think local service businesses and restaurants.