I love “Back to the future” as much as the next girl, but we have to admit by now that time travel (and even interdimensional travel like in Rick and Morty, is a flawed plot device.)
Rick and Morty is an awesome show. I will not deny that. I love it. I love the adventures the two get in, but the portal device is a to powerful magic wand, for anyone to wield.
It is stated many times in the show that it can travel to “infinite” dimensions. Infinite is a big number. It is never stated what those infinite dimensions consist off. So, for sake of argument, let’s consider that there is a dimension that is a second ahead of this one.
In that dimension, Morty has already seen the consequence of something that happened a second before the one I am in now. Dan Harlan did a great thing by creating multiple Morties and Ricks to circumvent this, but he also created his own flaw again, by killing a Morty and Rick from another dimension.
In one of the episodes Rick fucks up a love potion for Morty and travels to another dimension, kills the Rick and Morty there and leaves the fucked up dimension to be. This is lazy storywriting in my opinion. Yes, the problem is fixed for our duo, but it is a cop out.
Let’s say for example in the Harry Potter universe, a whole episode is devoted to Harry having diahhrea, but somebody comes along and fixes the problem with a magic wave. The magic is to powerful if there is no rules set for it and no rules will ever be good enough to fix time travel.
This is why in my opinion the Harry Potter series was fucked when she introduced time travel into the series, because why should we read any further to see what happens to Harry and his fight with Voldemort? First, they could travel to the future to see what happens. Second, they can travel to the past and kill voldemort, making the whole problem moot in the first place. Rowling tried to fix it in the play (or the 8th book) by putting restrictions on it, but still… not strong enough. Because there must have been wizard that was strong enough or will be strong enough to wield the power of time travel, or create a time traveling trincket (with the elderwand, the most powerfull wand).
Same goes for Back to the future. Future Marty knows that the car Past Marty is traveling with is damaged, so why not travel over to Past Marty and fix the car, making the whole first film absolete.