The younger generation doesn't necessarily fear conflict. Just look at how it's winning the conflict about conflict against the older generation.
They (we) want to reduce these kinds of negotiation because they give an economic advantage for entirely arbitrary reasons: someone getting a car cheaper because they negotiated harder or getting a better job offer because their trust fund allows them to walk away with ease does in no way benefit society. Whatever they save, someone else has to pay extra to make the system work for the dealerships.
Worse, the ability to negotiate is not some random variable. It's tied to aggressiveness and a sense of entitlement. It's a lifelong rebate for bullies that practiced that sort of thing by stealing younger kids' lunch money. And the only reason it has survived as long as it has is because that happens to be the demographic car salesmen also hail from.
Worst, it isn't even just about someone's ability to assert themselves: a salesman may well react entirely different to the same exact words and behavior based on criteria that would invoke laws against discrimination in other cases. I remember a number of stories of black homeowners being quoted 30 % when having their homes' resale value assessed. Don't remember seeing any tests for car sales, but I'd be surprised if it didn't replicate there: be a white broad-shouldered tall good-looking man and your lowballing makes you a strong opponent. Lack any of those criteria and it's considered an insult to the profession and you get the cold shoulder.