Probably nothing.
You would need an international law expert to be sure of the exact consequences, but if you have failed to pay a court ordered file then you would probably be unable to travel to an EU country or a country with an extradition treaty. You would certainly face issues if you ever wanted to expand your business overseas.
If you are serious about working in a terminal, then I highly recommend learning modern replacements for the old tools.
In this case ripgrep (or rg) https://github.com/BurntSushi/ripgrep is phenomenal. Especially for searching recursively in a large directory tree it is unbelievably quicker than regular grep.
It won't be installed on any random machine, so grep is still useful, but if you regularly need to text search in files then there are better tools.
In an odd twist of fate, a lot of the cheaper operators (e.g. iD mobile, Lycamobile, Giffgaff) still have free roaming in the EU+.
The fact that Kbin is handling the wave worse than Lemmy is not unrelated to the fact that Lemmy's tech stack is much lighter weight and more efficient. It is a fundamental issue with the technology. If either are going to become major players then they need exponential growth, and Lemmy is just better at that.
A lot of people seem to be talking about whether PHP has enough developer support, but that isn't the main issue.
The issue is that code written in PHP is probably at least 10 times less efficient in terms of CPU and memory than the equivalent code written in Rust.
This means that loads of hobbyist developers will be able to run lemmy instances for a fraction of the ongoing cost of kbin.
Why do you want to create a user there? I imagine it will reopen eventually, but you are likely much better off creating a user elsewhere.