This perhaps will do much more than the CHIPS act to remove the geopolitical risk associated with TSMC/Taiwan. A rational US administration would encourage this kind of development rather than stubbornly try to revive the sector domestically.
So, basically TSMC as a corporate entity's profits/revenues can keep chugging along. Taiwan itself continues to have a risky/uncertain future.
Most of the US subsidies are going to Intel (including for them setting up their foundry services which directly competes with TSMC). However there are some for TSMC for setting up in the US, that is true.
Until you can match labor cost with automation, it's DOA, regardless of how good your fabs are, and the automation isn't there yet.
Also remember the tooling is a fixed cost, it'll cost you (many) millions in Taiwan the same as it will in Japan or the US, so the cost of skilled labor is what ultimately affects your margins.