I’ve owned two previous models of Nikon Coolpix. Generally been happy w the cameras, but always disappointed in slow autofocus and number of out of focus shots.
I just checked CNet review of the P900 and they wrote “The autofocus system can be hit or miss and is slow to focus in low light.” Seems like they haven’t improved that. CNet also wrote that P900 is heavy w the big lens.
Last year I stepped up to an Olympus OM-D and love it. Very pricey though.
I have trouble taking good low light photos with my Nikon camera as well. I think my Fujifilm camera did a better job, but it only had 12x zoom.