This is a thing I run into a lot. I see it mirrored quite a bit in ADHD spaces, but it's most likely a general human thing. When asked why I did something, I explain. Whether the person accepts that as reasonable or not will generally dictate whether they call that a reason or an excuse. If it's reasonable to them, it's a reason. If it's not reasonable to them, it's an excuse.
Words are weird like that. They don't tend to have fixed meanings outside of technical jargon. Take the word "jerk" as one example. What one person considers being a jerk another would consider being perfectly normal. Some people see calling someone on their BS as being a jerk, others see it as perfectly normal. It all depends on culture and context.
The internet has shined a spotlight on just how fractured and divergent cultures and contexts are. The idea of universal codes of conduct for a large and diverse gathering of people is nonsensical on its face. Something even as seemingly simple as "don't be a jerk" means wildly different things to different people, cultures, and contexts. To say nothing of adding neurodiversity into the mix.