Bruh Top Rank had all them money names @ 147 years ago and made no attempt to work with the PBC (Bradley was Spences mandatory and could have forced that fight, Marquez was called out by all the PBC fighters, everyone wanted to face Manny). Arum said he would NEVER work with Haymon (You can find video of this). Spence is 1 of their Top 3 fighters, they got fights for him at 147-154 for the next couple of years. That's just the way it is.
We should have got Wilder vs Fury already but Top Rank blocked it to give us Otto Wallin, and Tom Schwarz. Even after all this Wilder still gave Fury a 50/50 Split for the second time (If they fight again after that it will be 60/40 to the winner).
You talk about side of the street but I haven't heard an actual offer to any PBC fighter. If that number ever does come out compare it to what Mickey Garcia, Thurman, and Porter made in tier last fights. If the PBC only had Carwford, and Top Rank had everyone else you think they would be making that fight?