I doubt it would be a total ban for all companies doing IPO overseas. Most probably the West is scaremongering.
However if this is true then that says to me that the CPC is gearing for protracted economic warfare against the West by shoring up its compehensive national strength. This means that China wants to become a strong financial center similar to the US and attracting funds from around the world.
Again, if what he is saying true, then the CPC is gearing for total confrontation on the economic front.
Westerners are going to lose it when they see how fast China makes decisions when under threat. Popcorn!
Adding on to that is the issue of the Party's total control of all final decisions and prevention of so-called Chinese liberals from establishing alternative power base. In fact, some of the most anti-CCP Chinese citizens are CEOs from these successful private firms and their families with overseas properties and residential permits. The last thing these successful entrepreneurs want is for any government (not just the CCP) to raise their taxes and force them to redistribute their wealth. Since the United States known for its small regulatory government, relatively low corporate tax, and protection of private properties (especially for the rich), it is only natural for these folks to not just move their assets/family members to the US, but also become the loudest neoliberal economic and political voices in China. The Clinton Administration was not wrong when he said that as the Chinese grew richer, they would demand bigger say in politics to protect their property rights, so potentially kick-start the process of demanding greater checks and balance against the CCP's monopoly of political power. After the death of the Tiananmen generation (intellectuals and urban workers), the loudest neoliberal voices today are the rich folks who earned their wealth outside of the CCP's institutions. Just think of Jack Ma daring to call for less financial regulations right in front of Wang Qishan and criticized the Party's regulations before the CCP got ticked off and killed ANT's IPO. And then look at the rich Chinese families desperate to send their kids and wives overseas (especially the US).
Therefore the dilemma for Xi and the CCP is that while they need successful Chinese bourgeoisie (successful private businesses, especially in the tech and finance sectors) outside of Party system to create enough job opportunities and continue to innovate for the country as a whole. Yet, these very successful people - as they grow richer - would demand more political power and better protection against redistribution of their wealth, while having their family members becoming the citizens of adversarial nations as another source of protection and leverage for themselves. As of today, Xi appears to be willing to take some short-term punishment in employment and innovation in order to solidify political control and prevent these wealthy private entrepreneurs from forming alternative power base (backed by the US) that challenges the CCP. In fact, these wealthy private entrepreneurs are also likely to have connections with other factions within the CCP, so for Xi, it is also a matter of taming political infighting in addition to maintaining control and monopoly of the Party's power.