I agree that it can be a chore, but more like, I'll use a real computer for serious tasks like doing my taxes, administration, planning vacations, etc.
But if you aren’t technical and everything is done online, then it’s easier for non-techies to do it on their phone.
This is still the case for non-techie Millennials and older. But for the younger generations who might have grown up with a smartphone as their only personal device, the distinction of task importance determining the platform has disappeared.