It's the same reason I was nervous moving our company domain to a .ai TLD; your entire presence, identity and trust is now beholden to the whims and political winds of a Caribbean island smaller than Topeka.
It's not anymore: "in April 2026 the implementation of the agreement was put on an indefinite hold due to opposition from US President Donald Trump." So whatever ICANN was going to do with .io, it's all on hold for now.