It takes time and people have been making 64bit OS's for Pi's.You think now that the Pi is 64-bit Distros will start making ARM editions for the RasPi4?
The Pi hardware has been 64bit compatible for several years already. If nothing has appeared by now, best not to hold your breath.
Raspberry Pi Foundation need to support ALL their products.
Hey if you want, you can go off and use BuildRoot to make your own OS.
Lots of behind the scenes stuff has been going on to get the Pi's into mainstream Linux.
The Buster version has lot of Pi stuff in it.
Now that people can get Pi4's I expect the next version of Debian to include even more stuff, perhaps.
Debian is just one of many Linux Distributions and Raspbian a a version of Debian.
There is some bias, as Linus is not known as a big fan of ARM.
Can someone please send him a Pi4B4
What other "Desktop" Computer is there that allow you to swap OS's in minutes?
That includes boot time.
Try them all, then try them again in 6months.
I was running Ubuntu Mate on Pi's years ago.
Hmm had to check - May 2015, wonder if it is any better, that was before Pi3?
Time flies, 4 years ago.