If you're referring to the logos, I think you're being a little harsh. The retro logos are only used with programmes of an archival nature. I can't see a problem with that. It's rather endearing.
idents used by BBC Two nowadays are "retro", to a greater or lesser extent!
(*with the possible exception of any "window on the world"-era ones (for they were the last true "new look") that may still survive in the current hotch-potch mix?)
Window on the World was scrapped by the end of 2014 - but the car crash of BBC TWO presentation it's left behind (the ugly endboards, inconsistency) is still lying around on the road, waiting to be taken to the crusher.
The last remnant of any Window on the World ident was the Christmas 2011 pres but that's been butchered with terrible singing.
Looking back on Window on the World - it wasn't bad. I particularly liked some of the idents and the soundtracks, especially Seascape and Mirror.
What ruined the set was an ugly endboard with garish and bright colours, and the idents were out of place with what was a more lighthearted but crap piece of presentation. Alt J's music made the idents a tad worse.
What also didn't help it was that it was lacked wit. Just as much as the Personality '2's were way too lighthearted and not serious enough, Window on the World was too much of seriousness in the way. Both have a sodomising problem of having too much of one aspect of TWO but completely missing the other. The damage control made by Keating over how the new pres package for TWO would 'embody its playful and fun personality' makes for amusing and ironic reading.
The 2007 '2' reeked of ugliness as well compared to the '2' that was unleashed with the excellent 90s idents - the differences are stark.
I'm sure that the 90s idents were dug out not only as a stopgap before the next refresh (DQF and Charter Renewal might be a cause) but one of an act of desperation - Window on the World was hacked off to bits throughout its lifespan.
Should the BBC really decide to rebrand TWO - I'd just hope that they'd try to emulate the 90s idents - and embody a BBC TWO for the modern age, with a balance of wit and seriousness, rather than having too much of one which hampered both the Personality '2's and the Window on the World pres packages' appeal. You only need to look as far as the excellent Artsnight ident to see how well it can be done.