My understanding is that schemes are often employed to shift profits that occurred in high tax regimes to lower tax ones. E.g. company registers their IP to sub

My understanding is that schemes are often employed to shift profits that occurred in high tax regimes to lower tax ones. E.g. company registers their IP to subsidiary in <low_tax_nation>. That subsidiary charges crazy royalties for the rest of the company to use the IP in <high_tax_nation>. The effective earnings in the high tax regime is low or zero because of the “cost” of licensing the IP. Meanwhile the subsidiary in low tax land makes bonkers profits on some extremely lucrative licensing. You can try to shut down these shenanigans playing legal whack a mole, but the law moves slower than the corporations. Or you can just set a global floor on taxes and not have to worry about keeping up with the latest corporate nonsense.