When a foundry wishes to raise capital from the private or public markets, it's bucketed under TMT - which includes software and fabless hardware as well.

This means it's almost impossible to raise capital without a near monopoly and/or government support and intervention - which is what Taiwan did for TSMC and UMC - because the upfront costs are too high and the margins are much lower compared to other subsegments in the same sector.

This is why industrial subsidizes like the CHIPS act are enacted - to minimize the upfront cost of some very CapEx heavy projects (which almost everything Foundry related is).