If by liking that you wished them a happy birthday do you mean they basically said “thanks”?
Well, that’s also just the polite response and etiquette. It’s what I do on the odd occasion someone says HB to me. It’s an automatic response, nothing more.
Just like if someone was to say to me “today’s my BD” of course i’d Say HB because it’s just polite.
However, if someone says that next week is my BD, my response would be “Oh”, or “Really?” Because it’s acknowledging what they said. If an adult tells me that, or volunteers it’s on a specific day, I’m thinking it’s usually in relation to something else going on, not like they’re fishing for future birthday greetings.
Having to type out the why’s and when a birthday is acknowledged is taking ever so much more time than that thought process behind it.
I show my true loved ones in ever so much more huge and deep ways of my devotion to them.
It’s definitely not through some trite public display.