My RPi will be used at home (as a Wifi radio unit), without any screen / keyboard / mouse, etc.
So very often, me, wife or kids will turn it off by just unplugging the power unit.
Will this be a problem on long term that the Linux Raspbian is not properly turned off ? (with shutdown command...)
Edit : This topic is more dedicated to RPi without screen / keyboard / mouse, so I cannot ask people using it to power off properly (such as described here : How do I turn off my Raspberry Pi?).
The only reason for a safe shutdown is that you risk corruption of any writable filesystem, so ideally you would minimize the system to something that easily runs on a read-only filesystem and retrieve media/etc from the network.
Going fully r/o would be a duplicate of this:
Make a read-only OS image from working installation
With a logging filesystem that is conservative (but Raspbian uses ext4 data=ordered which is in the middle) combined with a storage controller that is honest (and flash controllers often are not!) you would never risk an inconsistent filesystem state, yet might still not avoid drops to single user mode. (The system may want to ask or inform you about the selected state.)
With the ext4 in data=ordered mode like Raspbian's default, you may get some inconsistency, and similarly you also have applications that may have written inconsistent states to files with what they need to start (no differently than if they each crashed.)
Personally, I expect to get a reason why the system wont return to its normal runlevel and operation in about 1 out of every 12-20 unsafe boots on r/w media. For a system that collects no data, I would just keep the master image on another system and routinely write/rewrite a couple identical SDcards.
