I would say the online trophies for pole positions and 92 victories in GT Sport are a big reason why races are often a mess. People keep tanking their ratings to get these trophies and use dirty tactics to get the victory. Then of course they are addicted to the easy victories while sandbagging and continue. Instead of trophies for pole positions and victories, PD should have added trophies for clean races and maintaining high SR rating.
I don't bother with trophies and achievements anymore. They pop up, I ignore. Last gen I did sometimes chase trophies but it never improved the game. X kills with this weapon... just play the way you want to. Games have enough to do lists build in already. Going after a trophy basically means the game is lacking fun, looking for something to do instead.
I don't think they ever spoiled any plot points for me, can't remember. What I do find a bit spoilery is indeed those journals and ability pages you fill in while playing. You can already see what's coming and how much is left.







