Not a problem per se. But coming from phones with raised power buttons (easy to find without having to look at) or which give a slight vibration when booting and start after a two or three second button press, having to find the FP6’s recessed power button and press it until the display shows a sign of life, it’s a bit annonying to me. And when holding it with my right hand, I tend to also involuntarily press the lower volume button at the same time, which leads the phone booting into bootloader mode.
Normally I have this phone switched off. So whenever I use it, I have to power it on. Not too often, but again, it could be faster and simpler.