A simple single node is often more reliable than a complex fault-tolerant setup. Fewer moving parts mean fewer broken pieces.
Similar with security. A simple monolith is more secure than isolated front- and backend.
Similar with security. A simple monolith is more secure than isolated front- and backend.
Even if they don't, there is usually a huge tax on developer productivity with these architectures, which often outweighs any improved stability over the long term.
Let's keep in mind that modern hardware and software is very stable, generally.
Not at any significant scale. dimm will fail, power will be down, disks will need replacement.
It is all about risks after all. If you are ok to have couple of hours of downtime if one of the memory sticks stops working - good for you. But generally any large enough business won't tolerate such risks.
I'm not saying that the cloud is the answer, but I don't see any future for single instance solution. And if you design your system like this, you are taking much more risks than necessary.
...except when your single piece breaks and you get your whole service down. Then what?