The best possible brand connotations are an interesting way of putting it. When you are trying to get a company off the ground (figuratively) that is experimental in nature and will require a lot of capital investment, why hinder yourself with this 'bad' name right out of the gate? There are any number of edgy names they could have picked that people didn't associate with the last thing you want to have happen on an airplane. It is just unnecessary, and not well thought out. Even if the intent was to get attention, I wonder how many people at Boom talked to the founders and said: "Are we sure about 'Boom'?"

I didn't associate it with anything negative the first time when I saw the headline. Didn't even think about it being a bad name till I read the comment.

Not sure as many people will think it is negative as you think.

Well, what they think when they first see it, and what they think after it's made the rounds of the late shows (Kimmel, Colbert, Fallon, etc) might be entirely different. This is low hanging fruit.

What are some positive associations with booms?

Case in point: Soylent

I still don't get that name choice. I'm guessing it's tongue-in-cheek, but in the back of my mind I still can't help wonder whether it'll turn out to be some sick prank. Then, it's like "well, it was right there on the label".

I know the chances of that are next to nil, but why even put that image in potential customer's heads?

Brands? Who cares? Are they the cheapest, fastest etc? I don't care which characters constitute their name, nor which bitmap they've chosen for their current logo.

You don't have to care about it, it was just pointed out for you a possible reason for the name. You can go on and care about the price, speed, etc now.