That's the point, even the biggest nerds out there with too much free time and no actual life to fill it sooner or later get older and grow up, and stop living in the past and going back to decades old titles the world has forgotten,
But still, regarding the servers being shut down - that's not going to happen, like, ever, unless something will flop completely, and by completely I mean something like let's say Stadia not being able to actually penetrate the market, at all within next 5-7 years, as there would be nothing to lose for Google, but for all of the services that are already there for years/decades and are well established, it just won't happen, they are there primarly to milk money on a monthly/yearly basis, not for a "quick" cash grab and disappear in 5 or 10 years, That would be catastrophic for any public company, as A) they would lose their main/only source of income, B) they would completely lost their customers and would never be able to regain them, C) the stocks would go downhill AF. It's simply not within the companies interest to start those services and shut them down later on, and the longer it lasts and the bigger the customer base gets, the harder it would be for them to actually perform a shut down, without serious injuries, including mass lawsuits from both the customers and the investors. In other words, shutting down a service might as well ended up with shutting down the entire company.
Removing individual titles or disabling their online components, now that's a different story, but then again, today's 100GB is yesterday 10MB, the memory copacity of the servers is drastically going up every single year, so in theory there would be no point for the companies to remove 10/15/20yo games, as their size would be laughable compared to the service capacity at the given time.
And on a personal note, I find that digital is actually more future-proof, as the games stay with your account, as oppose to old consoles people most likely sell once a new generation shows up, and all the games for the old console along with it. Especially as you mentioned, a console sooner or later will fail to operate, and the same way the optical discs will also sooner or later fail to work, as oppose to servers that have everything backed up. Sure, putting everything in the publishers hands is a risky move, but as I mentioned, it's withing their very own best interest to keep those services and games going. I mean, Steam, XBL, PSN etc. are already almost two decades old, and so far so good to say the least.
