TSMC in the US is a bit of a special case .... wouldn't surprise me at all if they were virtue signalling to the Trump admin more than anything with what they are doing there.
If they do diversify, they are compromising a key policy protecting their homeland, it makes no sense!
Trump did do the initial deal though, but TSMC had to cough the money up for that
TSMC wouldn’t put tens of billons of dollars in irreversible investment just to virtue signal, the scale is too large
You can’t “undo” a fab