For me, the issue with Sokol-Lubrizol was the timing of his Lubrizol share purchases. IIRC, Sokol bought those shares just weeks prior to bringing the deal to Buffett.
To me, it's different situation vs Buffett-SRG/Munger-BYD/Weschler-DVA/Lou Simpson - Cort furniture.
Those people have had investments in those companies for years prior to Berkshire's involvement.
IIRC Buffett said when Sokol told him that he had purchased Lubrizol shares, Buffett thought Sokol meant he has owned the shares personally for a while, Buffett didn't ask him when Sokol bought the shares.