Two details stand out to me:
1: Regarding "healthy competition", software development has long been plagued with unproductive hyper-competitive work environments. Places where rewriting a co-worker's perfectly good code using an obscure trick to be slightly shorter was considered a valuable way to determine who was the top dog. The book Showstopper, about how Windows-NT was written is a nice example. The Code Golf StackExchange is a reminder of those days.
That hasn't been stamped out yet, and any hint of artificial competition or jockeying for who's the best is going to remind people of that toxic, easy-to-slip-into work environment they want to avoid.
2: I'm assuming you have some Com Sci training, but web developers may not. Say you see them use A.remove(fn1).map(w=>w.toUpper). Pretty advanced stuff, right? In a Com Sci program this is proof you've thoroughly learned the dozen concepts and features involved. But a boot-camp might start with that and cover only how to write things of that form (which can solve 97% of day-to-day problems, after all).
You may be proposing things assuming they're a bit rusty on them, or are stubbornly refusing to do it that way. But they may never have done anything close, have no way of judging good or bad, and wouldn't be able to maintain it without you. The best you may be able to do is learn what they know and don't know, figure out how to express some new ideas using their language, and make sure whatever "black magic" parts you write interface nicely with their system.