While I agree spending with Ishbia changed things, rumors were Cam's camp turned down offers in the range you quoted. So at the time it was Sarver, and the money was a no go, or we would have signed him. Now the debate is, is KD > Cam? Yes, and that is why he was included in the deal. In fact KD is perceived to be > Cam + Bridges.
Technically we could afford him, but he was need to get KD so it's a moot point. But if he had been kept by us, yes we could afford him even with Beal as long as we traded Ayton.