That's true in the UK, for most pilots.
For those who walk around with mobile internet, it is probably more convenient. Whether it is "easier" for IFR is doubtful because the whole Eurocontrol business has made the actual filing operation rather moot, because it is preceeded by a fairly involved process of getting a valid route.
Also, I think it is true everywhere outside the UK that you
can simply write out a flight plan on the paper form and hand it in. The time that falls over is when there is nobody around at the airport
