My feeling is that it’s just basic good design and if your game engine can already save player progress then implementing autosaves is relatively cheap.
James Arthur, Ubisoft
Players often do not know that a section will be problematic for their particular impairment (such as a quick time event) until they come across it, meaning a quick death and having to replay without a recent manual save in place – a particular issue if you have a motor impairment that already makes play lengthy and difficult.
It can also be useful for conditions such as ADD that affect likelihood of remembering to save.
Ideally provide both autosave and manual save.
Best practice example: XCOM: Enemy Unknown