It was a few years between seasons 2 and 3 of Borgen, and for me watching retrospectively it was also a couple of years; this was not by design but rather due to my lack of excitement for the show. The second season was solid, but it again seemed to live too much on the surface of everything, and while it was enjoyable and had good elements, it felt like wish fulfilment for an audience of a certain political bent (one I share). I watched the third season because it was there, if I am honest. I remembered the ending of the second season, but this isn't picked up so much as skipped forward from. The plot this season sees Birgitte returning from industry for a failed run at leading the Moderates, and when that fails she sets up her own party and the season goes from there.
As a narrative, the season mostly produces the same politics as before - with its liberal slant and element of fantasy in its content and characters. It is interesting but not too engaging as things go. The moments of drama and tension are often undercut by other elements of the plotting or of the delivery. The weaknesses include elements or threads that don't really go anywhere important; mostly these are melodrama around the characters' families, affairs, health, or a combination; they don't impact so much as fill - and while they have some value due to our investment in the characters, that is all that is keeping them up. The performances are solid throughout - although it only really sparks when Knudsen and Sørensen are together. Outside of this not everyone else is firing as they should; in some cases major characters feel like they fitted this season into their schedule of other work. Credit to the many new characters introduced only for this season - they worked pretty well and the cast are mostly to be thanked for that.
As a whole though, this final season is uneven. It does enough for those that loved the previous seasons - but for viewers like myself (who think the show is okay but not more) then it also continues in that vein without shaking much up or challenging for more.