All of those absolutely help, at the cost of added complexity, additional points of failure, and hardware/VPS costs. And you still risk losing data, or at least data integrity.

Not to mention there are still hard limits on how quickly you can insert data into a database with 100% durability (which is, of course, impossible, but another topic entirely), and there are scales where even these mitigation tactics can't help you anymore (in particular, online casino games have this problem since they are persisting the state of multiple players very frequently).