I think the negative replies to your post are mostly due to the trivialization of what is most likely a nontrivial skill. You say that you are not going to do any actual bartending, and don't seem interested in bartending as anything other than another skill to put in your toolbelt. But then you say "I don't want to be yet another bartender - I want to be something above that". Very likely the people on that subreddit are offended by the implication that their skill can be learned to this extent just as a side-hobby and not as a profession.

You also don't explain how bartending can help you with science or vice versa, or even how the two are related at all, and you call yourself a nerd in a tribal-affiliation sort of way that doesn't add to the discussion at hand. In some of your responses you come very close to claiming you are superior to everyone else (e.g., "I might have not worded it so clearly, but personally I find it important to excel in whatever I do").

Finally, for better or worse, an overly-verbose "putting on airs" style of writing is often looked down upon on the internet (especially in responses to criticism, I've noticed). It can come off as patronizing to some people. This is likely why someone linked to /r/iamverysmart as a response, as your post most closely pattern-matched with it in their mind.

I hope I don't sound rude with this reply; no one on Reddit responded to you when you asked why you were getting such confrontational replies, so I thought I would offer some constructive criticism.