It's a crap plot point whether it was in Bill and Ted or Doctor Who.
"Sensible response of the primary characters given they have time-travel capability" does not equal "crap plot point" unless you ENJOY seeing people deliberately and stupidly NOT remembering the blindingly obvious.
But then, you do come from a city that voted for Boris Johnson as Mayor, so perhaps...
Why the insults?
It's not that sensible to use that as a plot point in a time travel series. Why don't they use it every episode?
The Doctor is in peril but it's ok because a future version will pop in to tell a major supporting character how to solve this week's puzzle.