Stephen E. Shay (Boston College; Google Scholar), The Deceptive Allure of Taxing "Residual Profits", 75 Bull. Intl. Taxn. 527 (2021):

This article outlines the traditional justifications for a residual profits business tax base and evaluates its role in the OECD/G20 Pillar One proposal to allocate income to market countries. The article concludes that basing the allocation of profits to market countries on multinationals’ residual profits would be inferior to allocating a portion of total corporate profits.

Conclusion
Taxing residual profits garners enthusiasm on the drawing board, but it has yet to deliver on the promise held out by economic theory. The allure is deceptive in relation to the reality. The allure is even further removed in relation to Pillar One. There does not appear to be a compelling reason to import residual-profit taxation into the Pillar One regime.