Why would you close Twitter, Github and onther similar services? All the data there is already public, so moving somewhere else and make it public again won't change anything regarding privacy.
As far as other public social sites go, they capture far more data about you than the status update, etc.
I pay for private GitHub hosting.
I use GitLab extensively and it has an acceptable level of friction:value for me.
It's possible to use both Twitter and Github in a less public fashion.
the point is not that its public - the $point seems to be that its too easy for a spy agency to directly access the data. yours and the data of many many many (ok everybody) others who use these services