For MONETARY purposes yes, as well as rating purposes in the WBA. Holding the WBA "title" essentially guarantees it's holder a mandate with current WBA Super Champion, Wlad Klitschko. And any unification fights outside the WBA would give said fighter leverage in negotiation vs the other titlist, ie Wilder atm. So in those terms, yes, I personally consider Chagaev a WBA "titlist" and will Browne should he beat Chagaev. Whichever is victorious will have themselves a solid Win over a top 20, and be in great position for big fights.:think
I'm a fan of Browne, but even a fat unmotivated(possibly shot) version of Chagaev is still too much for him to handle.
Chauncy Welliver has seen both Chagaev and Browne up close and personal and Welliver believes Browne will be the victor. So I think Browne has a reasonable chance of winning. It's not like Chagaev has looked like the Terminator in his most recent fights.:think