The last few days I have been using Linux, AROS (Hosted), and TOS+MiNT+XaAES+fVDI+Thing-Desktop, and I have found that I have been less productive than when I use RISC OS and TOS+MiNT+XaAES+fVDI+Thing-Desktop. And booting RISC OS in an emulator is not worth it, as it is too slow (I really wish that RPCEmu had an ARM to ARM JIT).
As AROS/Amiga OS are inline with what everyone calls modern Operating Systems, as is Linux, this goes to show that productivity does not always line up.
In TOS+MiNT+XaAES+fVDI+Thing-Desktop I get a good deal done, though that is when I have time to use it and am not fighting with Linux and AROS.
In RISC OS I get a lot done without having to fight for anything. RISC OS is likely where I am the most productive, with the TOS+MiNT setup being where I am second most productive. There is nothing to fight with for ordinary usage in RISC OS, and I feel that this is a key point. The configuration is taken care of by a very small number of shell scripts (known as Obey Files in RISC OS) at boot (not like the Linux maze of scripts plus config files), the OS does not fight you to do simple things, and it is fast and out of the way.
Then there is the fact that in RISC OS there is not usually any issues of dependency when programming, or when adding an application. The only thing that slows me down at all on RISC OS is the lack of an ARMv8 compliant C compiler that I can afford (and is not gcc), as I do not have the money to update my copy of the DDE.
TOS+MiNT is another very simple system, even though it is a bit Unix like in nature. TOS+MiNT all the config is done by running the Auto folder programs until reaching MiNT, then MINT.CNF runs the rest. The other configuration files are simple short and minimal in number, including MMU config, user configs, path configs, desktop configuration, VDI configuration (in fVDI.SYS) AES configuration, and network config.
TOS+MiNT also avoid the issue of dependency in most cases. And there is a good up to date C compiler for these (AHCC). Everything about TOS+MiNT is great the way that it is, including the GUI (evolved from DR-GEM, though super up to date). I must admit that TOS+MiNT is ahead of RISC OS, the only downside being that TOS+GEM is 68K native still to this day, I think it is time to get back to the ARM port work to finally have a truly modern OS that runs on the RPi.
All said RISC OS has a huge advantage advantage, over the other OS's that can run native on the ARM and RPi series, when it comes to actually getting stuff done.