Facebook disappearing tomorrow would cause a bit of a kerfuffle but life would go on.
Same for Google search.
But if VISA disappeared, there'd be hell to pay.
In reality none of these companies will disappear overnight, but they could get remaindered pretty quickly, because they're not that "important" per se.
That's not to say the companies don't do things and people don't find value, but Facebook disappearing is an entire different class of thing from Exxon-Mobil shuttering.
You are grossly underestimating how many business rely on Google and Facebook.
A small example: a ton of delivery companies depend on Google maps API for localization and route planning - think Doordash, Uber, etc. Not just that, lots of transit agencies and freight companies use Google API for planning and optimization. Half of the work force probably can't reach their destination without Google maps.
I'm pretty sure many critical components of Exxon-Mobil depend on some tools provided by Google.
It'd probably be more straightforward than that. Your bank would switch over their cards to Mastercard, and send you a new one in the mail. I don't even think it's inconceivable that the Mastercard card # range is salvaged and you can retain the same card number.
To regular users, yeah, the impact would be tough but materially trivial (maybe?). But to the small businesses for which FB, Instagram, and Google advertising are their primary sources of customers? Devastating.
Same for Google search.
But if VISA disappeared, there'd be hell to pay.
In reality none of these companies will disappear overnight, but they could get remaindered pretty quickly, because they're not that "important" per se.
That's not to say the companies don't do things and people don't find value, but Facebook disappearing is an entire different class of thing from Exxon-Mobil shuttering.