I can't speak for game trailers, but for most movies, once you see the trailer you have seen everything in the movie worth watching. I assume the same for games.
Usually, yeah. There's a reason why most game trailers... at least, the the trailers for big expensive games... show almost entirely cinematics, and very little gameplay.
What's worse is that the vast majority of "big" games like that are predatory. As in, they prey on people with addiction issues, getting them to spend bat&$@# amounts of money AFTER the initual $60 purchase. There are people out there that have spent THOUSANDS on ONE game. It's THAT bad. Not to mention stories of things happening like kids completely draining their parents' bank account (again, usually on ONE game).
It's all about that greed. The big publishers will do ANYTHING to get more money, if they think they can get away with it. I'm guessing that this is the case in plenty of different industries, not just gaming. But it seems to be worse in gaming because lawmakers are.... well... dinosaurs. They're often the "how do I delete my emails, my computer is so slow" and "what's a gif" sort of tech user. So they're utterly clueless on tech, and the related laws are dirt slow to catch up. I dont even do politics myself... I dont touch that subject with a 300000000-foot pole, and even I know how clueless those twits are.
And then on top of all of that, games like the one in the trailer have one other issue: licensed games are almost always legendarily terrible. Like, the worst of the worst. Reason: people WILL buy it based on the name / intellectual property used in the game. It wont matter worth a crap if this Terminator game is good, or if it's beyond terrible: People WILL buy it, they WILL pre-order it, and no amount of negative reviews will sway them. It's freaking Terminator, and that's all it needs.... and those companies know it. Most likely, there wont be much effort put into it outside of those cinematics. Games like these are also often very glitchy.
There's exceptions to that rule of course, but they're incredibly rare.
All of this is why I dont play AAA games anymore. Just.... just no. Well, aside from Nintendo's stuff. They dont seem to have succumbed to the dark side yet.