Could Future Trunks's future be saved?


One of the recurring questions in the original Dragon Ball Z manga was if
Future Trunks's future could have been restored somehow.

Obviously the story was carefully made to remove the Earth Dragon Balls from
the picture, but that would still leaves the New Namek version as an option.
"Lucky" since Goku is dead that also removes the possibility for Trunks to
know that New Namek exists in the first place.

But then Trunks comes to the present timeline. And everyone in that timeline
knows that Namek still exist, with its set of Dragon Balls.

This in turn creates a question: is there any reason Trunks couldn't just get
the information about Namek new location from the present timeline, get a
spaceship from present day Bulma and get present Piccolo or even Dende to come
with him to the future Namek and ask them for help?

Notice that this becomes even weirder if you consider that in Super Trunks has
somehow made contact with the Kai but he still hasn't tried using the Namek
Dragon Balls to resurrect everyone.

Dragon Ball once implied some weird time limit for resurrection, but that
seems to apply only to evil people (because after a while their soul is
cleansed and reincarnated).

Is there any other reason I am missing or is this a case of "we don't care,
the cursed timeline is an useful plot device so it stays that way"? (which is
kinda odd since thanks to Xenoverse 2 even Akira should be aware that "most
time patrolers want to keep the happy future timeline going").

Also worth noticing that Team Four Star _**did**_ reference this in the
arbriged version: Bulma tries to find the new Namek but fails. Why she
couldn't just ask to the _past_ Z Fighters is still an open question.

Therefore, to summarize: _**is there any actual reason Future Trunks could not
have learnt the position of new Namek from the present timeline Z-Fighters and
then used a spaceship from present Bulma to reach the planet (maybe with some
of the present timeline characters tagging along to be recognized) and ask the
Namekian for help, either to restore the planet or resurrect the people killed
by the androids?**_




**For the Cell Saga**

Future trunks could've traveled to Namek, using Vegeta's spaceship. Since
Trunks was born and raised on Earth implies Vegeta came on Earth, and he
could've easily used his spaceship or Bulma could've repaired it if needed
since she's depicted as a brilliant person when it comes to technology, to
travel to Namek, if Kami wasn't there on Earth for some reason. Trunks
could've easily gotten Namek's location from Picollo or others from the
present day.

**For Zamasu's erasure as well**

Z-fighters could gather Super Dragon Balls from their timeline and revive
Trunk's universe. As Super Dragon Balls have been shown to revive universes,
not sure about Earth's Shenron's power regarding this.

He could've used present-day's Shenron as well, to recreate the same, as
reviving the planets and dead is within reach of Shenron's powers.

One more thing is that the concept of timelines isn't straight in Dragon Ball,
as changing the past, just creates a new timeline, which doesn't follow the
space-time continuum.

I think Future is left as is, just in case new arcs are required (like they
created Cell Saga in Z and Goku Black in Super), as having a similar timeline
would remove that possibility, like which Goku to shine in that case.

