Sayyid `Abd ar-Rahman al-Jifri and the others mentioned are socialists; the government probably sees them as the intellectual descendents of the rulers of South Yemen,which they aren't. In fact, the `Ulama of Hadramawt like Habib `Umar (the teacher of Habib `Ali) did not support the south Yemen reigime either. Indeed the communists murdered Habib `Umar's father, who was the Mufti, while Habib `Umar was quite young. Habib moved out of south Yemen to al-Bayda' where he studied at the Ribat there. Habib `Ali grew up in Jeddah with the other `Ulama of Hadramawt (Who escaped South Yemen). Habib `Umar travelled to the Haramayn to do the bulk of his learning (19 years I think) in the company of Habib `Abd al-Qadir, Habib Ahmed, Habib `Attas and Sayyid Muhammad b. `Alawi.
As a side note, the Yemeni government is pretty corrupt and selfish, so I wouldn't trust it.