Lots of distributions have niches in which they excel. I've been ssh'ing into a couple of CentOS servers that have been excellent.
If the range of Linux distributions is too much for you to get your head around and you need a single monolithic "best" operating system, maybe Windows is more your speed.
the reason kubuntu is objectively the best distribution is due to KDE being the most complete environment, and Ubuntu base having the largest user base, meaning bugs are picked up and wiped out FAST.
It may be when you install it for the first time.
Total time sunk fixing my install after some shit breaks: maybe 2-4hrs
Total time sunk shitposting on /g/: over 99999hrs
You're gonna waste ur time on some pointless crap anyway, why not use it for actually something useful like learning how to linux
Kde usually takes a few years to get usable after a major upgrade and kde5 is not there yet.
They have crippled widgets to get more people to use activities, their new theme has weird spacing issues, their logout promt has no hotkeys anymore, the GUI for top is no longer built in to Krunner and the calendar no longer shows your events.
But they have added an option to remove the cashew (which is now a menu icon) and the built in file search is now useable.
I feel I have to use it at this point because no other desktop has Krunner.