First thing it downloaded a 10 or 20 Gb patch...
Here is one website keeping track of it happening to various degrees: https://delistedgames.com/
Sometimes the game simply disappears from the store front but you can find it in your library. Sometimes it disappears from your library too, and you can request it via some process (https://delistedgames.com/get-your-games-back/). Sometimes you need to write the company in order to get a new key to whatever platform it is still available.
And sometimes it's just lost, with no recourse.
I have hundreds of video games. On steam I think it's over 200 titles. I can't tell if something I purchased ever disappeared from there. What I do know is I have lots of titles on my account that aren't sold on Steam anymore. Some GTA games with the original soundtrack, several EA titles that used to be sold on Steam once upon a time.
Is there a way to use this site to check my gaming accounts to see if I lost any games?
If you buy a single player game digitally you should continue to have access to it for the life of the console as long as you aren't banned for doing something like disputing a credit card charge. (Which admittedly is a concern.)
Nobody bought P.T.
The Scott Pilgrim game was delisted on the Ps3 when the license expired, and I can still download and play it today. Being delisted just means new customers can't buy it.
There's no way Sony's terms of service allow developers to pull games from the library after purchase, that would be a remarkable business failure on their part given how much leverage they have in negotiating the TOS with developers.
I returned a faulty game as is my legal right under UK law, Steam said they didn't allow that because they had their own much more restrictive rules. Eventually, I raised a PayPal dispute and PayPal choose to refund me (the amount was ~£1). They retaliated with restrictions to my account ... such restrictions as retaliation for fair exercise of rights granted by law is something that needs addressing.
I've noticed that game libraries, like Steam, now explicitly try to remove consumer rights with a click-thru pseudo-contract that directly contradicts UK law (roughly 'you give up rights to a refund'; whilst the Consumer Rights Act explicitly applies to digitally supplied goods).
Just thought this was a related point of note. Suppliers of intangible media have a little too much free rein.