Honestly, I think my lack of issue with spoilers when it comes to Dragon Ball comes from the time period I got into it. I first became a fan when Toonami was airing re-runs of the tail end of the Freeza arc, leading in to a premiere of the Androids arc material shortly enough there-after. So in my case, I dived into a franchise that was already more than halfway through it's major story points, so to more fully understand things, I had to read online about all of the previous material. In doing that though? I also ended up reading about all of the material after that as well, from the Boo arc onward through GT. As a result, Dragon Ball has ALWAYS been about spoilers for me. It's always had this weird give and take of 'read about something and then get to see it for myself at some point after that'.
It held true in the newer era as well - I was here reading about Battle of Gods before I'd get to see it, same with Resurrection 'F'. Super was the one weird case where for the most part, I was able to see it with my own eyes almost immediately after it came out, but even there, a lot of the time I'd be reading Herms' reviews and peoples comments on the latest episodes over the weekend (since I work over the weekend), only to end up getting to see the episode myself Monday or so. And now with Broly, I'm again at the mercy of what people say online until I can see it for myself later on. It's just...what Dragon Ball is for me.
That said though, I do realize how differently so many people feel about spoilers, so if I'm talking about the series somewhere else like Facebook for example, I try to not say anything too spoiler-y if I can avoid it. Stuff like Toei's marketing strategy, or lack there-of, though, does lead to some issues with even that. I shared the Gogeta trailer without even thinking about how some people might not want to see that. Since it came out from an official source, my brain didn't even register it as a 'spoiler', it was just an advertisement for me. So in the vein of trying not to spoil others who might not wish to be spoiled, their mass release of constant new footage and info does make it a little difficult for me to talk about the series with others without spoiling things for them.