I think this is mainly because all of what you describe has been available as FOSS software for a long time, just not wrapped into a single browser based package. So there is little reason to reinvent the wheel when you actually have better specialized tools available.
I think this is mainly because all of what you describe has been available as FOSS software for a long time, just not wrapped into a single browser based package. So there is little reason to reinvent the wheel when you actually have better specialized tools available.