Very true. But Sony always manufactures and supports the previous generations consoles until the next gen consoles enter manufacturing. For example, the PS2 ended production when the PS4 first started entering production to free up resources for PS4. Also what happened is any remaining servers for PS2 multiplayer games started shutting down. I don't think there's any PS2 games that can be played online anymore. I see when PS5 enters production the same thing will happen. Granted most servers for PS2 were independent, I just can't see Sony putting money and resources in a 2 previous generation console (which includes server space for games) that only a small niche group of people are still using. They already kind of started shutting things down for PS3 too. For example, MAG was a PS3 game. Sony shut down the game to free up resources on their servers. Now the game is completely useless. You can't buy or find anything for it in the PS Store.
Only good thing is there is PS Now so you can play older games. Though the thing that would suck is you are paying for a game a second time that you already have owned through a digital download

And I really hope you're right that they leave the games available for download on a PS3 for many many years to come. Only time will tell. The answer will come once PS5 enters the picture. Either way, I have my discs so I never have to worry about this except for the free games I downloaded for PS+ and a few indie download only games I bought. But I also backup my PS3's hard drive a couple times a year so if it does crash, I lose nothing except some saves