The logic is this
The biggest variable in the performance of a wheel is the tyre
Whether that variable is aerodynamic, feel, grip or anything else – tyres make a huge difference, so for example a tyre with a stiff carcass on a stiff wheel feels terrible to ride etc.
Rumour was that in the testing of the CXR aero road wheels they tested a load of different tyre tread, and the different airflow could make about 20% difference to the overall drag of the wheel as a unit.
Now, obviously theres a shit load of marketing and profit margin calculations in there, but when you get down to marginal gains there’s certainly some logic to dealing with the whole thing rather than leaving this huge variable out there.
(to be fair, things can be gotten wrong too, there was talk going on about certain front tyres on the rear to give better grip etc – I think one of the biggest challenges is that if you get a tyre right for ‘where you research’ then it might not work in another area, so some of the tyres were supposedly great on french tarmac but terrible in other places as the blend of tar and stone is different)