All good questions!! I guess it depends on the capacity of the holodeck to formulate scenarios based on the information it had. Could it create new scenarios or was it stuck with what was on the phone? It would have only gone so far in Laura's life and wouldn't have any information past 2015. I wonder if Gordon could have looked up the rest of her life somewhere.
I did like the point that Malloy made about people who lived in the past, that their time to them was just like our time is to us.
A hundred years from now people will wonder what life was like in 2019, just like we might wonder about life in 1919, or any other past time period. Their view of day to day life was just like ours.
If Malloy looked up the rest of her life (which he could have), then wouldn't the rest of the simulation play out exactly as it did on earth?
But if the holodeck could create new scenarios, then it could be like an alternate timeline. After all, the events that Malloy attended were extrapolated from the phone data and they weren't exactly as it happened on Earth. Laura never had some dates with Gordon or slept with him.
In
DS9, when Vic Fontaine's program was continually running, it took on a life of its own and anything could've happened. Even in
Voyager, the Doctor effectively gained sentience and had a life of his own and experienced emotions. He was very different both from the original Dr Zimmerman on whom he was based, and the other EMHs on other ships.
Although we compare this to previous Star Trek episodes, this episode was actually quite similar to a
Twilight Zone episode as well. Particularly the bit where Gordon deletes Greg and then thinks he can finally have the life he wanted with Laura, but realises that it was Greg who encouraged her to come out of her shell and perform in front of others. So she was no longer the person Gordon fell in love with and he realised he had to give it up and put it all back to what it was. That's just the sort of thing that
the Twilight Zone would've done.
But then many of the best Star Trek episodes (particularly the original series) are very similar to the Twilight Zone anyway, especially with all their social commentary and plot twists. That's what I feel is severely lacking in
Star Trek Discovery. There's never been any episode that has felt like
the Twilight Zone.