I poorly paraphrased profits converge to zero under perfect competitive market. Yes real world not perfect competitive markets. Oligor/duo/monopolies form, sometimes subsidies other shenanigans pick winner(s), winners extract huge margins/rents to build moats lock out new competition. Sometimes they collude / settle on business model with higher margins, i.e. 10-20% being normal/commodity, 50% for software and semi is top end of luxury goods. New state backed competitor enters and decides they can live on 10% margin, and then incumbants business model falls apart unless state also steps in to match.

E: And state can, but I don't know if state generally willing/able to backstop companies to 50% margin long term. I can't think of any, maybe some major state oil. Nvidia/TSMC with $$$ margins getting some CHIPs injection really meant for bailing out broke ass Intel was already anomalous, and it was basically to bribe them to onshore production.