Again, that's not what the law states. The law is not broken when someone is alarmed or distressed by a comment. The law is broken if you post something that is "likely or intending to" which is not judged by the victim. If you walk into a police station in England and tell them that this comment on Hacker News alarmed and distressed you, it doesn't matter, it is up to the legal system to judge my intent, i.e: whether my comment was "likely to" or "intending to" cause alarm and distress.

Whether you agree with the law or not, it is important to be accurate when discussing it. The U.S. vs. U.K. (not) free speech law discussion online so often seems to frame them as fundamentally different, but they are on the same spectrum. The go-to example of the limits of free speech in context of the U.S. legal system is "Shouting fire in a crowded theater". The U.K. laws are the same in principle but a little further along the spectrum.