What is the normal temperature for a Dell Inspiron 15 7000 when playing a demanding game like Assassin's Creed Origins? Mine goes up to a maximum of 93°C according to Intel XTU. Even when using a cooling pad. Should I be worried?
Long term operation at that temperature isn't going to do the longevity of the system any favors, no. Reduce the load on the system - and remember this is an entry-level gaming system, so it will have limitations particularly with demanding game.
I would be uncomfortable depending on long term reliability with those temperatures - but if you've got a 3-year warranty (which should be part of any notebook purchase), at least it's Dell's responsibility for that period of time.