If Bojack Unbound took place after the Cell games and Trunks came back from the dead, shouldn't his power have undergone a drastic change from it since he is a saiyan. Saiyan's power increase after recovering from a near death experience so he should have been on a level similar to Gohan yet he had a difficult time with Bojack men(and woman) let alone Bojack himself.
Movies are not meant to be part of the canon, so they don't give a shit about timelines and making sense. Not to mention Trunks died, so no Zenkai boost for him. Vegeta should be a fkn monster after all the near death beatings he has taken though.
Doesn't a Saiyan also get a zenkai boost after being revived from death? Remember Vegeta mentioning something about it, but that might've been anime only. Other than that yeah.
During the Cell Games, after Goku transported him to King Kai's planet in Other World killing Goku, King Kai, Gregory and Bubbles also destroying King Kai's planet in his self destruct mode. Then he comes back as Super Perfect Cell and shoots Trunks point blank to the chest and Trunks killing him in the process.
TBH I'm not entirely sure, but I always believed it had to be a near death experience. I don't see or remember any instance of zenkai boosts working after people coming back from the dead(They usually just train in the afterlife--or rather just goku lol) I could be wrong though, so yeah.
I heard somewhere that the sole purpose of zenkai was to help saiyans level up to the point that they could become super saiyans and afterwards they no longer receive this boost. Two exceptions to this are Cell and Brolly but they're two oddities.