Yes, I believe there is too much hype here surrounding these migrations to XHS. It's an amusing event, but not that significant.
In addition to what you wrote about the negligible percentage, young Americans who decided to sign up to XHS are either apolotical or with pre-existing China-friendly attitudes. It's not like China managed to convert millions who were previously hostile to China or anything like that.
The significance is not in the sheer number. It was the moment of shock and awe when the first person dared to pull the thick curtain to let in the light. Had Trump not paused the ban for TT to resume its service in less than 24 hours, there would have been more than 5 millions seeking asylum in XHS.
But as the saying goes in Chinese, 星星之火 可以燎原 (a few sparks can turn a whole valley into ashes). There ought to be more than just a few "sparks" in these 5 million TT refugees. There was even a young lady sharing her excitement about studying the 矛盾论 (On Contradiction, a work of Mao and a must read for all CPC members).
Many of the TT refugees were hardly "pro-China" when they came to XHS. Once they had the exchange with the Chinese people on XHS, they openly admitted that they had been fed anti-China propaganda by the US government and the western MSM for decades, and only realized how wrong they had been thinking of China and Chinese people.
Trump might have
unintentionally slowed down the increase of TT refugees for now. But ironically, his intervention, at the cost of the rule of law, is allowing those awakened refugees to share their discoveries on TT to a broader audience, encouraging and convincing more TT users to take a look outside.
For those who decide to not stay on XHS, as long as they have learned to not accept anti-China propaganda without thinking about it critically, it is a win for China already.
In 1938, Mao wrote 论持久战 (On Protracted War) for those who were expecting an easy and quick win against Japan and those who were losing confidence in defeating the Japanese. Substituting the Japanese militarism with American Imperialism, and the war against Japanese aggression in China with the struggle against American hegemonism on the world stage, his line of thinking still stands today.
The burst of a great dam is significant so is the first crack on the dam even if the crack is a much less eye catching scene. And dams do not fail on the first crack.