Twitter can move of course. But it still needs Silicon Valley VC money. It still makes massive losses. Plus it may feel it still needs the infrastructure of suppliers and pool of staff to use.
Also it does rather well from the exemption it got from the US gov for responsibility for what it publishes. As do Google and Facebook. By continuing the lie that they're not publishers. Other jurisdictions may not be generous or easygoing. If it was so easy, how come almost all the tech giants are US based?
It's clearly possible of course. But the US government still has them by the balls if lots of their execs are citizens and ever want to go home, or a majority of their revenue comes from US sources.
Any government with a sufficiently large economy can make waves internationally by targetting payments to companies that piss them off. This is a major component of foreign policy now, and is one of the main reasons why Iran made that nuclear deal - i.e. international pressure on its companies and trade. It's also why the Russian economy has suffered so badly from relatively light sanctions over their invasion of Ukraine. Because they've been targetted at screwing over their banking oil and gas sectors.