Carbon leakage is here with us. It is difficult to translate, it is certainly not a carbon leak, but rather the threat of businesses escaping to countries where they do not have European rules for dealing with CO2. At one of the conferences on the subject, it was said that there was no evidence or studies to illustrate this in any way. Just look at the data provided by Worldsteel to see how much less steel is produced in the EU-27 compared to the growth in China over the last ten years.

The EU-27's share of global steel production fell from 10.9% to 7.8%. At the same time, China's share rose from 45.6% to 52.9% (as pictured in the graph). So carbon leakage unfortunately exists.

https://worldsteel.org/steel-topics/statistics/world-steel-in-figures-2022/