With the new EU flight compensation rules, this data is becoming increasingly important. Websites such as Flightradar24 have historical records of flight tracks including takeoff and landing, but they don't actually track the flight all the way to the gate.
At a minimum, I do need to know the actual departure and arrival times for the flight, in order to fill in the EU compensation claim form.
https://ec.europa.eu/transport/sites...nt_form_en.pdf