The phrase "activist rather than" is correct and usable in written English.
It can be used to compare two different roles or identities, emphasizing a preference for one over the other.
Example: "She identifies as an activist rather than a passive observer in social issues."
Alternatives: "advocate instead of" or "campaigner rather than".
That's because the former senator has the instincts of an activist, rather than of a president or statesman.
I'm willing to believe all these things, but in the end Geldof is an activist rather than a strategist.
There is more glamour working as an animal rights activist rather than as a mental health rights activist.
Worthy as these may be, they play to the view of Labour as the party of the underdog and hand-wringing activist rather than one uniting around key messages, embodied in the figure of the leader.
The Republican pollster and message strategist Frank Luntz, who is close to Cantor, Ryan, and McCarthy but has feuded with Boehner, says that the Young Guns "hope that he will be a conservative activist, rather than just a conservative traffic cop.
He not only admitted in 2010 and 2011 that he failed to anticipate the massive carnage and destruction the invasion would wreak but also viewed the invading U.S. soldiers as "ministering angels" and "liberators". Does that make him an activist rather than a journalist?
Labour MPs fear their activists rather than their voters.
The book's detractors were generally polemicists or activists rather than artists.
This ensures that the activists, rather than the government, keep setting the agenda.
As for Mr Abeid, he remains in custody in Mauritania, which seemingly prefers to crack down on anti-slavery activists, rather than slavery itself.
There is evidence that the activists rather than the leader may be out of step with the people who might vote for them.
