Semantically you are correct, contextually it had the potential to be rude. Words morph and twist in meaning all the time, based on context and individual interpretation. It was not that weird to apologise for calling someone entitled. It is often used as an insult.
Lots of people feel entitled to free, clean, potable tap water. Lots more people don’t because they live somewhere without it.
There is nothing wrong with saying, “our product is not for people entitled to X”. There is no judgement there, let alone anything negative.