The traffic levels are odd at the moment and seem to vary day to day, my schedule has been different this week and I've been walking to Brixton at different times between 7.45am and 8.30am along CHL and I have seen much more traffic than in your pictures, but then Fridays are always quieter as it's a popular work at home day. Traffic numbers do seem to be quite inconsistent, whether that is people still investigating new routes or less cars on the road full stop, I don't know.
What I can say is that Brixton Road, along the main stretch definitely seems to be busier and that is very unpleasant, much like CHL was when the temporary traffic lights were still in. And the junction of Gresham Road and Brixton Road is taking forever. I beat 5 buses on foot on Wednesday from Western Road to the tube station, I don't think the buses had even got round the corner. That is a problem, the cars have different options as to routes taken, buses don't and if you're going beyond the tube station, that stretch can add a good 20 minutes to your journey in the morning, more if you're on the 35 as that has to get all the way round the one way.
In some ways, I would say that the one group of people that have been affected by the closures the most is bus users, bus journeys going through Brixton are taking much longer, especially going towards Brixton, the reverse journey is not so bad. I often used to take the bus to Brixton as I'm a lazy so and so but now unless I've got lots of bags or it's chucking it down, I walk, it just takes too long.
More anecdata for the pot I guess