As far as I know, Global Foundries ceased efforts at 7nm and lower because they could not afford it.
They had previously signed a contract with IBM to produce silicon at these more advanced nodes that they could not honor, and there was legal action between them.
https://www.anandtech.com/show/13277/globalfoundries-stops-a...
https://newsroom.ibm.com/2025-01-02-GlobalFoundries-and-IBM-...